Systems and methods for creating an effect using microwave energy to specified tissue

ABSTRACT

Systems, methods and devices for creating an effect using microwave energy to specified tissue are disclosed herein. A system for the application of microwave energy to a tissue can include, in some embodiments, a signal generator adapted to generate a microwave signal having predetermined characteristics, an applicator connected to the generator and adapted to apply microwave energy to tissue, the applicator comprising one or more microwave antennas and a tissue interface, a vacuum source connected to the tissue interface, a cooling source connected to said tissue interface, and a controller adapted to control the signal generator, the vacuum source, and the coolant source. The tissue may include a first layer and a second layer, the second layer below the first layer, and the controller is configured such that the system delivers energy such that a peak power loss density profile is created in the second layer.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/252,109, filed Aug. 30, 2016, now U.S. Pat. No. 10,166,072; whichapplication is a continuation of U.S. application Ser. No. 12/107,025,filed Apr. 21, 2008, now U.S. Pat. No. 9,427,285; which applicationclaims priority under 35 U.S.C. § 119(e) to U.S. Provisional ApplicationNo. 60/912,899 filed Apr. 19, 2007; U.S. Provisional Application No.61/013,274, filed Dec. 12, 2007; and U.S. Provisional Application No.61/045,937, filed Apr. 17, 2008. All of the above priority applicationsare expressly incorporated by reference in their entirety.

application Ser. No. 12/107,025 also claims priority to PCT ApplicationNo. PCT/US08/060935, filed Apr. 18, 2008; PCT Application No.PCT/US08/060929, filed Apr. 18, 2008; PCT Application No.PCT/US08/060940, filed Apr. 18, 2008; and PCT Application No.PCT/US08/060922, filed Apr. 18, 2008. All of the above PCT priorityapplications are also expressly incorporated by reference in theirentirety.

BACKGROUND Field of the Invention

The present application relates to methods, apparatuses and systems fornon-invasive delivery of microwave therapy. In particular, the presentapplication relates to methods, apparatuses and systems fornon-invasively delivering microwave energy to the epidermal, dermal andsubdermal tissue of a patient to achieve various therapeutic and/oraesthetic results.

Description of the Related Art

It is known that energy-based therapies can be applied to tissuethroughout the body to achieve numerous therapeutic and/or aestheticresults. There remains a continual need to improve on the effectivenessof these energy-based therapies and provide enhanced therapeutic resultswith minimal adverse side effects or discomfort.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of a cross-section of human tissue structures.

FIG. 2 illustrates a system for generating and controlling microwaveenergy according to one embodiment of the invention.

FIG. 3 illustrates a system for delivering microwave energy according toone embodiment of the invention.

FIG. 4 is a side perspective view of a microwave applicator according toone embodiment of the invention

FIG. 5 is a top perspective view of a microwave applicator according toone embodiment of the invention.

FIG. 6 is a front view of a microwave applicator according to oneembodiment of the invention.

FIG. 7 is a front view of a tissue head for use with a microwaveapplicator according to one embodiment of the invention.

FIG. 8 is a cutaway view of a tissue head according to one embodiment ofthe invention.

FIG. 9 is a side cutaway view of a microwave applicator according to oneembodiment of the invention.

FIG. 10 is a top perspective partial cutaway view of a microwaveapplicator according to one embodiment of the invention.

FIG. 11 is a side partial cutaway view of a microwave applicatoraccording to one embodiment of the invention.

FIG. 12 is a cutaway view of a tissue head and antenna according to oneembodiment of the invention.

FIG. 13 is a cutaway view of a tissue head and antenna according to oneembodiment of the invention.

FIG. 14 is a cutaway view of a tissue head, antenna and field spreaderaccording to one embodiment of the invention.

FIG. 15 is a cutaway view of a tissue head, antenna and field spreaderaccording to one embodiment of the invention.

FIG. 16 is a cutaway view of a tissue head, antenna and field spreaderaccording to one embodiment of the invention.

FIG. 17 is a cutaway view of a tissue head, antenna and field spreaderaccording to one embodiment of the invention.

FIG. 18 is a cutaway view of a tissue head, antenna and field spreaderaccording to one embodiment of the invention.

FIG. 19 is a cutaway view of a tissue head, antenna and field spreaderwith tissue engaged according to one embodiment of the invention.

FIG. 20 is a cutaway view of a tissue head and antenna and with tissueengaged according to one embodiment of the invention.

FIG. 21 illustrates a tissue head including a plurality of waveguideantennas according to one embodiment of the invention.

FIG. 22 illustrates a tissue head including a plurality of waveguideantennas according to one embodiment of the invention.

FIG. 23 illustrates a tissue head including a plurality of waveguideantennas according to one embodiment of the invention.

FIG. 24 illustrates a disposable tissue head for use with an applicatoraccording to one embodiment of the invention.

FIG. 25 illustrates a disposable tissue head for use with an applicatoraccording to one embodiment of the invention.

FIG. 26 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 27 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 28 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 29 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 30 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 31 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 32 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 33 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 34 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 35 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 36 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 37 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 38 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 39 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 40 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 41 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 42 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 43 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 44 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 45 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 46 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 47 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 48 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 49 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 50 illustrates a tissue profile according to one embodiment of theinvention.

FIG. 51 illustrates a tissue profile according to one embodiment of theinvention.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

When skin is irradiated with electromagnetic radiation, such as, forexample, microwave energy, energy is absorbed by each layer of tissue asthe electromagnetic radiation passes through the tissue. The amount ofenergy absorbed by each tissue layer is a function of a number ofvariables. Some of the variables which control the amount of energyabsorbed in each tissue layer include: the power of the electromagneticradiation which reaches each layer; the amount of time each layer isirradiated; the electrical conductivity or loss tangent of the tissue ineach layer and the radiation pattern of the antenna radiating theelectromagnetic energy. The power which reaches a particular layer oftissue is a function of a number of variables. Some of the variableswhich control the power reaching a particular layer of tissue includethe power impinging upon the surface of the skin and the frequency ofthe electromagnetic radiation. For example, at higher frequencies thepenetration depth of the electromagnetic signal is shallow and mostpower is deposited in the upper layers of tissue, at lower frequencies,larger penetration depths result in power deposition in both upper andlower tissue layers.

Heat may be generated in tissue by a number of mechanisms. Some of themechanisms for generating heat in tissue include resistive heating,dielectric heating and thermal conduction. Resistive heating occurs whenelectrical currents are generated in the tissue, resulting in resistivelosses. Tissue may be resistively heated using, for example, mono-polaror bi-polar RF energy. Dielectric heating occurs when electromagneticenergy induces an increased physical rotation of polar molecules thatconverts microwave energy into heat. Tissue may be dielectrically heatedby, for example, irradiating the tissue with electromagnetic energy inthe microwave frequency band. As used herein, microwave frequency bandor microwave frequencies may refer to, for example, electromagneticenergy at frequencies which are suitable for inducing dielectric heatingin tissue when that tissue is irradiated using an external antenna totransmit the electromagnetic radiation. Such frequencies may be in therange of, for example, from approximately 100 Megahertz (MHz) to 30Gigahertz (GHz). Whether tissue is heated by resistive heating or bydielectric heating, heat generated in one region of tissue may betransmitted to adjacent tissue by, for example, thermal conduction,thermal radiation or thermal convection.

When a microwave signal is radiated into a lossy dielectric materialsuch as water, the energy of the signal is absorbed and converted toheat as it penetrates the material. This heat is primarily generated byinduced physical rotation of molecules when subjected to the microwavesignal. The efficiency of the conversion of microwave energy into heatfor a given material can be quantified by the energy dissipation factor,or loss-tangent (tan □). The loss-tangent varies as a function ofmaterial composition and the frequency of the microwave signal. Waterhas a large loss-tangent and heats efficiently when irradiated withmicrowave energy. Since all biological tissue has some water content,and thus is lossy, it can be heated using microwave energy. Differenttissue types have varying amounts of water content, with muscle and skinhaving a relatively high water content and fat and bone havingsignificantly less water content. Microwave heating is generally moreefficient in high water content tissues.

The application of RF energy, which is conducted through the surface ofthe skin, or microwave energy, which is radiated through the surface ofthe skin, to heat tissue below the skin surface generally results in atemperature gradient having a peak at the surface of the skin anddecreasing with increasing depth into the tissue. That is, the hottestpoint is generally found at or near the surface of the skin. Thetemperature gradient results from the power lost by the electromagneticradiation as it moves through the tissue. The power loss density profilegenerally peaks in tissue at the skin surface and declines as theelectromagnetic radiation moves through the tissue, regardless of theradiated power or frequency of the electromagnetic radiation. Power lossdensity is measured in watts per cubic meter. An equivalentcharacterization of power deposition in tissue is the SpecificAbsorption Rate (SAR) which is measured in watts per kilogram. Specificabsorption rate in tissue may be, for example, proportional to thesquare of the magnitude of electric field in that tissue. For a fixedradiated power level the penetration depth will generally decrease asthe frequency increases. Thus, as a general principal, to heat tissuenear the skin surface, such as, for example, the epidermis, withoutdamage to deeper tissue layers one would generally select a higherfrequency. Further, as a general principal, to heat tissue deep withinthe skin, such as, for example, in the deep dermis or the hypodermis, orbelow the skin surface, such as, for example, in muscle tissue, onewould generally select a lower frequency to ensure that sufficientenergy reached the deeper tissue.

Where electromagnetic energy is being used to heat structures in tissuebelow the skin surface and it is desirable to limit or prevent damage tothe skin surface or tissue adjacent the skin surface, it is possible tomodify the temperature gradient to move the peak temperature deeper intothe tissue. Temperature gradients within tissue may be modified to movethe peak temperature into tissue below the skin surface by, for example,using external mechanisms to remove heat from tissue close to the skinsurface. External mechanisms which remove heat from the surface of theskin may include, for example, heat sinks which cool the skin surfaceand adjacent layers. When external mechanisms are used to remove heatfrom the surface of the skin, the heat may be removed as theelectromagnetic radiation deposits energy into that tissue. Thus, whereexternal mechanisms are used to remove heat from the surface of the skinand adjoining layers, energy is still absorbed at substantially the samerate by tissue adjacent the skin surface (and the power loss density andSAR in the cooled tissue remain substantially constant and are noteffected by cooling) but damage is prevented by removing heat fasterthan it can build up, preventing the temperature of the cooled tissue,for example, tissue adjacent the skin surface, from reaching atemperature where tissue damage occurs or a lesion could form.

FIG. 1 is an illustration of human tissue structure. In the embodimentof the invention illustrated in FIG. 1, muscle tissue 1301 is connectedto hypodermis 1303 by connective tissue 1302. Hypodermis 1303 isconnected to dermis 1305 at interface 1308. Epidermis 1304 lies overdermis 1305. Skin surface 1306 lies over epidermis 1304 and includessquamous epithelial cells 1345 and sweat pores 1347. Tissue structures1325 such as, for example, sweat glands 1341, sebaceous glands 1342 andhair follicles 1344, may be positioned throughout dermis 1305 andhypodermis 1303. Further, tissue structures 1325 may be positioned suchthat they cross or interrupt interface 1308. FIG. 1 further includesartery 1349, vein 1351 and nerve 1353. Hair follicle 1344 is attached tohair shaft 1343. Tissue structures such as, for example, apocrineglands, eccrine glands or hair follicles may be expected to have sizesin the range of, for example, between approximately 0.1 millimeter andtwo millimeters and may group together to form groups or structureshaving even larger sizes. As illustrated in FIG. 1, interface 1308 maybe expected to be a non-linear, non-continuous, rough interface whichmay also include many tissue structures and groups of tissue structureswhich cross and interrupt interface 1308. When modeling tissue layerssuch as, for example the dermis, it is difficult to accurately model thepermittivity (e.g., dielectric constants) and/or conductivitycharacteristics of the tissue layers because of the variability fromperson to person and within body regions of individuals. In addition,the presence of tissue structures and of groups of tissue structurescreates additional complexities. Assuming an average dielectric constantfor a particular layer does not generally reflect the complexity of theactual tissue, however, it may be used as a starting point. For example,assuming a dielectric constant of, for example, approximately 66 fordermal tissue at 100 MHz, electromagnetic energy at the low end of themicrowave range, would have a wavelength of approximately 370millimeters. Assuming a dielectric constant of, for example,approximately 38 for dermal tissue at 6.0 GHz, electromagnetic energywould have a wavelength of approximately 8 millimeters in dermal tissue.Assuming a dielectric constant of, for example, approximately 18 fordermal tissue at 30 GHz, electromagnetic energy at the high end of themicrowave range would have a wavelength of approximately 2.5 millimetersin dermal tissue. Thus, as frequency increases, the presence of rough,discontinuous interfaces between tissue regions and the presence oftissue structures and groups of tissue structures will result inunpredictable scattering of at least some of the signal when itencounters tissue structures, groups of tissue structures ordiscontinuous tissue interfaces. For a fixed size tissue structure,group of structures or discontinuity, scattering generally increases aswavelength decreases and becomes more pronounced when wavelength iswithin an order of magnitude of the size of tissue structures, groups oftissue structures or discontinuities in the interface. At lowfrequencies, the wavelength of the signal is long enough that it wouldreflect off the interface without substantial unpredictable scattering.

When electromagnetic energy is transmitted through a medium havingstructures and interfaces, including interfaces between tissue layers,the electromagnetic energy will, depending upon the electrical andphysical characteristics of the structures, groups of structures andinterfaces, and the differences between electrical and physicalcharacteristics of such structures, groups of structures and interfacesand surrounding tissue, be scattered and/or reflected by the structures,groups of structures and/or interfaces. When reflected electromagneticwaves interact with incident electromagnetic waves they may, undercertain circumstances, combine to form a standing wave having one ormore constructive interference peaks, such as, for example an E-fieldpeak, and one or more interference minimums (also referred to as regionsof destructive interference). However, scattering will tend to minimizeor destroy such constructive interference peaks.

In modeling tissue for the purposes of the present discussion dermaltissue may be modeled to include a dermis and an epidermis. In modelingtissue for the purposes of the present discussion dermal tissue may bemodeled to have a conductivity of approximately 4.5 siemens per meter atapproximately 6 GHz. In modeling tissue for the purposes of the presentdiscussion dermal tissue may be modeled to have a dielectric constant ofapproximately 40 at approximately 6 GHz. In modeling tissue for thepurposes of the present discussion hypodermal tissue may be modeled tohave a conductivity of approximately 0.3 siemens per meter atapproximately 6 GHz. In modeling tissue for the purposes of the presentdiscussion hypodermal tissue may be modeled to have a dielectricconstant of approximately 5 at approximately 6 GHz.

Systems and Apparatuses

FIGS. 2 through 25 and 48 through 51 illustrate embodiments andcomponents of embodiments of systems according to the invention whichmay be used to generate heat in selected tissue regions. FIGS. 2 through25 and 48 through 51 illustrate embodiments and components ofembodiments of systems according to the invention which may be used togenerate predetermined specific absorption rate profiles in selectedtissue regions. FIGS. 2 through 25 and 48 through 51 illustrateembodiments and components of embodiments of systems according to theinvention which may be used to generate predetermined specificabsorption rate profiles such as, for example, the specific absorptionrate profiles illustrated in FIGS. 26 through 51. FIGS. 2 through 25 and48 through 51 illustrate embodiments and components of embodiments ofsystems according to the invention which may be used to generatepredetermined specific absorption rate or power loss density profiles inselected tissue regions. FIGS. 2 through 25 and 48 through 51 illustrateembodiments and components of embodiments of systems according to theinvention which may be used to generate predetermined power loss densityprofiles such as, for example, the power loss density profilesillustrated in FIGS. 26 through 51.

FIGS. 2 through 25 and 48 through 51 illustrate embodiments andcomponents of embodiments of systems according to the invention whichmay be used to generate predetermined temperature profiles in selectedtissue regions. FIGS. 2 through 25 and 48 through 51 illustrateembodiments and components of embodiments of systems according to theinvention which may be used to generate predetermined temperatureprofiles such as, for example, the temperature profiles illustrated inFIGS. 26 through 51.

FIGS. 2 through 25 and 48 through 51 illustrate embodiments andcomponents of embodiments of systems according to the invention whichmay be used to create lesions in selected tissue regions. FIGS. 2through 25 and 48 through 51 illustrate embodiments and components ofembodiments of systems according to the invention which may be used tocreate lesions in selected regions by generating specific absorptionrate profiles with a peak in the selected tissue regions. FIGS. 2through 25 and 48 through 51 illustrate embodiments and components ofembodiments of systems according to the invention which may be used tocreate lesions in selected tissue by generating specific absorption rateprofiles such as, for example, the specific absorption rate profilesillustrated in FIGS. 26 through 51, wherein the lesion is created inregion of the tissue corresponding to the peak specific absorption rate.FIGS. 2 through 25 and 48 through 51 illustrate embodiments andcomponents of embodiments of systems according to the invention whichmay be used to create lesions in selected regions by generating powerloss density profiles with a peak in the selected tissue regions. FIGS.2 through 25 and 48 through 51 illustrate embodiments and components ofembodiments of systems according to the invention which may be used tocreate lesions in selected tissue by generating power loss densityprofiles such as, for example, the power loss density profilesillustrated in FIGS. 26 through 51, wherein the lesion is created inregion of the tissue corresponding to the peak power loss density. FIGS.2 through 25 and 48 through 51 illustrate embodiments and components ofembodiments of systems according to the invention which may be used tocreate lesions in selected regions by generating temperature profileswith a peak in the selected tissue regions. FIGS. 2 through 25 and 48through 51 illustrate embodiments and components of embodiments ofsystems according to the invention which may be used to create lesionsin selected tissue by generating temperature profiles such as, forexample, the temperature profiles illustrated in FIGS. 26 through 51wherein the lesion is created in region of the tissue corresponding tothe peak temperature. Further non-limiting examples of embodiments ofmicrowave systems and apparatuses that may be used and configured asdescribed above can be found, for example, at FIGS. 3-7C and pp. 8-13 ofU.S. Provisional App. No. 60/912,899; and FIGS. 3-9 and 20-26 and pp.34-48 and FIGS. 20-26 of U.S. Provisional App. No. 61/013,274 bothincorporated by reference in their entireties, as well as illustratedand described, for example, in FIGS. 3A-7C and pp. 16-20 of Appendix 1and FIGS. 20-26 and pp. 38-46 of Appendix 2.

FIG. 2 illustrates one embodiment of a system for generating andcontrolling microwave energy according to one embodiment of theinvention. In the embodiment illustrated in FIG. 2, controller 302 maybe, for example, a custom digital logic timer controller module thatcontrols the delivery of microwave energy generated by signal generator304 and amplified by amplifier 306. Controller 302 may also control asolenoid valve to control application of vacuum from the vacuum source308. In one embodiment of the invention, signal generator 304 may be,for example, a Model N5181A MXG Analog Signal Generator 100 KHz-6 GHz,available from Agilent Technologies. In one embodiment of the invention,amplifier 306 may be, for example, a Model HD18288SP High Power TWTAmplifier 5.7-18 GHz, available from HD Communications Corporation. Inone embodiment of the invention, vacuum source 308 may be, for example,a Model 0371224 Basic 30 Portable Vacuum Pump, available from Medela. Inone embodiment of the invention, coolant source 310 may be, for example,a OP9TNAN001 NanoTherm Industrial Recirculating Chiller available fromThermoTek, Inc.

FIG. 3 illustrates a system for delivering microwave energy according toone embodiment of the invention. In the embodiment of the inventionillustrated in FIG. 3, power is supplied by power source 318, which maybe, for example an AC mains power line. In the embodiment of theinvention illustrated in FIG. 3, isolation transformer 316 isolates themains power provided by power source 318 and supplies isolated power tocontroller 302, vacuum source 308, signal generator 304, amplifier 306,temperature data acquisition system 314 and coolant source 310. In oneembodiment of the invention, vacuum cable 372 connects vacuum source 308to applicator 320. In the embodiment of the invention illustrated inFIG. 3, signal generator 304 generates a signal, which may be, forexample, a continuous wave (CW) signal having a frequency in the rangeof, for example, 5.8 GHz and that signal is supplied to amplifier 306,which is controlled by controller 302. In the embodiment of theinvention illustrated in FIG. 3, an output signal from amplifier 306 maybe transmitted to an applicator 320 by signal cable 322. In oneembodiment of the invention, signal cable 322 may be, for example, afiber optic link In one embodiment of the invention, applicator 320 maybe, for example, a microwave energy device. In the embodiment of theinvention illustrated in FIG. 3, coolant source 310 may supply acoolant, such as, for example, chilled de-ionized water, to applicator320 through coolant tubing 324, and, more particularly, coolant may besupplied to applicator 320 through inflow tubing 326 and returned tocoolant source 310 through outflow tubing 328. In the embodiment of theinvention illustrated in FIG. 3, applicator 320 includes temperaturemeasurement devices which relay temperature signals 330 to thetemperature data acquisition system 314, which, in turn, relaystemperature signals by a fiber optic link 332 to the temperature displaycomputer 312. In one embodiment of the invention, isolation transformer316 may be ISB-100W Isobox, available from Toroid Corporation ofMaryland. In one embodiment of the invention, temperature displaycomputer 312 may be, for example, a custom timer controller developedfrom a number of off-the-shelf timer relay components and custom controlcircuitry. In one embodiment of the invention, temperature dataacquisition system 314 may be, for example, a Thermes-USB TemperatureData Acquisition System with OPT-1 Optical Link available from PhysitempInstruments Inc.

FIG. 4 is a side perspective view of a microwave applicator according toone embodiment of the invention. FIG. 5 is a top perspective view of amicrowave applicator according to one embodiment of the invention. FIG.6 is a front view of a microwave applicator according to one embodimentof the invention. In the embodiments of the invention illustrated inFIGS. 4 through 6, applicator 320 includes applicator cable 334,applicator handle 344, applicator head 346 and tissue head 362. In theembodiment of the invention illustrated in FIGS. 4 through 6, tissuehead 362 includes vacuum ports 342, cooling plate 340, tissue chamber338 and tissue interface 336. In one embodiment of the invention, tissuehead 362 may be referred to as a tissue acquisition head. In theembodiment of the invention illustrated in FIG. 5, tissue head 362includes alignment guide 348, which includes alignment features 352. Inthe embodiment of the invention illustrated in FIG. 6, tissue head 362is mounted on applicator head 346 of applicator 320. In the embodimentof the invention illustrated in FIG. 6, tissue head 362 includesalignment guide 348, alignment features 352 and tissue chamber 338. Inthe embodiment of the invention illustrated in FIG. 6, tissue chamber338 includes tissue wall 354 and tissue interface 336. In the embodimentof the invention illustrated in FIG. 6, tissue interface 336 includescooling plate 340, vacuum ports 342 and vacuum channel 350.

FIG. 7 is a front view of a tissue head for use with a microwaveapplicator according to one embodiment of the invention. In theembodiment of the invention illustrated in FIG. 7, tissue head 362includes alignment guide 348, alignment features 352 and tissue chamber338. In the embodiment of the invention illustrated in FIG. 7, tissuechamber 338 includes tissue wall 354 and tissue interface 336. In theembodiment of the invention illustrated in FIG. 7, tissue interface 336includes cooling plate 340, vacuum ports 342 and vacuum channel 350. Inone embodiment of the invention, tissue head 362 is detachable and maybe used as a disposable element of a microwave applicator such as, forexample, applicator 320.

FIG. 8 is a cut away view of a tissue head according to one embodimentof the invention. FIG. 8 is a cutaway view of a tissue head 362 andantenna 358 according to one embodiment of the invention. In oneembodiment of the invention, antenna 358 may be, for example, awaveguide 364 which may include, for example, waveguide tubing 366 anddielectric filler 368. In the embodiment of the invention illustrated inFIG. 8 antenna 358 is isolated from cooling fluid 361 in coolant chamber360 by standoff 376. In the embodiment of the invention illustrated inFIG. 8, chamber wall 354 has a chamber angle Z which facilitates theacquisition of tissue. In the embodiment of the invention illustrated inFIG. 8 tissue interface 336, which may include cooling plate 340, has aminimum dimension X and tissue chamber 338 has a depth Y.

FIG. 9 is a side cutaway view of a microwave applicator according to oneembodiment of the invention. FIG. 10 is a top perspective partialcutaway view of a microwave applicator according to one embodiment ofthe invention. FIG. 11 is a side partial cutaway view of a microwaveapplicator according to one embodiment of the invention. In theembodiment of the invention illustrated in FIGS. 9 through 11,applicator 320 includes applicator housing 356 and tissue head 362. Inthe embodiment of the invention illustrated in FIGS. 9 through 11,applicator housing 356 encloses applicator handle 344 and at least aportion of applicator head 346. In the embodiment of the inventionillustrated in FIGS. 9 through 11 applicator cable 334 includes coolanttubing 324, inflow tubing 326, outflow tubing 328, signal cable 322 andvacuum cable 372. In the embodiment of the invention illustrated inFIGS. 9 through 11, vacuum cable 372 is connected to vacuum splitter374. In the embodiment of the invention illustrated in FIGS. 9 through11, applicator 320 includes antenna 358. In the embodiment of theinvention illustrated in FIGS. 9 through 11, antenna 358 may includewaveguide antenna 364. In the embodiment of the invention illustrated inFIGS. 9 through 11, waveguide antenna 364 may include dielectric filler368 and waveguide tubing 366. In embodiments of the invention, coolingchamber 360 may be configured to facilitate the continuous flow ofcooling fluid 361 across one surface of cooling plate 340. In theembodiment of the invention illustrated in FIGS. 9 through 11, signalcable 322 is connected to antenna 358 by antenna feed 370, which may be,for example a distal end of a semi-rigid coaxial cable or a panel mountconnector and includes the center conductor of the cable or connector.In the embodiment of the invention illustrated in FIGS. 9 through 11,applicator 320 includes tissue head 362. In the embodiment of theinvention illustrated in FIGS. 9 through 11, tissue head 362 includestissue chamber 338, chamber wall 354, cooling plate 340 and coolingchamber 360. In the embodiment of the invention illustrated in FIGS. 9through 11, cooling chamber 360 is connected to inflow tubing 326 andoutflow tubing 328. In the embodiment of the invention illustrated inFIG. 10, vacuum cable 372 is connected to secondary vacuum cables 375.In the embodiment of the invention illustrated in FIG. 10, secondaryvacuum cables 375 may be connected to vacuum ports 342 (not shown) intissue head 362.

In the embodiment of the invention illustrated in FIG. 11, vacuum cable372 is connected to secondary vacuum cables 375. In the embodiment ofthe invention illustrated in FIG. 11, secondary vacuum cables 375 may beconnected to vacuum ports 342 (not shown) in tissue head 362.

FIGS. 12 and 13 are cutaway views of a tissue head and antenna accordingto one embodiment of the invention. FIGS. 14 through 18 are cutawayviews of a tissue head, antenna and field spreader according to oneembodiment of the invention. FIG. 19 is a cutaway view of a tissue head,antenna and field spreader with tissue engaged according to oneembodiment of the invention. In the embodiments of the inventionillustrated in FIGS. 12 through 19 antenna 358 may be, for example, awaveguide antenna 364. In the embodiments of the invention illustratedin FIGS. 12 through 19 waveguide antenna 364 may comprise, for example,waveguide tubing 366 and waveguide filler 368 and may be connected tosignal cable 322 by, for example, antenna feed 370. In the embodimentsof the invention illustrated in FIGS. 12 through 19 tissue head 362 maycomprise, for example, tissue chamber 338, chamber wall 354, coolingplate 340 and cooling chamber 360. In the embodiments of the inventionillustrated in FIGS. 12 through 19 cooling chamber 360 may includecooling fluid 361.

In the embodiment of the invention illustrated in FIG. 12 antenna 358 isisolated from cooling fluid 361 in coolant chamber 360 by standoff 376.In the embodiment of the invention illustrated in FIG. 13 at least aportion of antenna 358 is positioned in coolant chamber 360. In theembodiment of the invention illustrated in FIG. 13 at least a portion ofwaveguide antenna 364 is positioned in coolant chamber 360. In theembodiment of the invention illustrated in FIG. 13 waveguide antenna 364is positioned in coolant chamber 360 such that at least a portion ofwaveguide tubing 366 and dielectric filler 368 contact cooling fluid 361in coolant chamber 360.

In one embodiment of the invention illustrated in FIG. 14 field spreader378 is positioned at an output of waveguide antenna 364. In oneembodiment of the invention illustrated in FIG. 14 field spreader 378 isan extension of dielectric filler 368 and is positioned at an output ofwaveguide antenna 364. In one embodiment of the invention illustrated inFIG. 14 field spreader 378 is an extension of dielectric filler 368extending into coolant chamber 360. In one embodiment of the inventionillustrated in FIG. 14 field spreader 378 is an extension of dielectricfiller 368 extending through coolant chamber 360 to cooling plate 340.

In one embodiment of the invention illustrated in FIG. 15 field spreader380 is integrated into dielectric filler 368 of waveguide antenna 364.In one embodiment of the invention illustrated in FIG. 15 field spreader380 is a region of dielectric filler 368 having a dielectric constantwhich differs from the dielectric constant of the remainder ofdielectric filler 368. In one embodiment of the invention illustrated inFIG. 15 field spreader 380 is a region having a dielectric constantwhich is in the range of approximately 1 to 15.

In one embodiment of the invention illustrated in FIG. 16 field spreader382 is integrated into dielectric filler 368 of waveguide antenna 364and extends into coolant chamber 360. In one embodiment of the inventionillustrated in FIG. 16 field spreader 382 is integrated into dielectricfiller 368 of waveguide antenna 364 and extends through coolant chamber360 to cooling plate 340. In one embodiment of the invention illustratedin FIG. 16 field spreader 382 has a dielectric constant which differsfrom the dielectric constant of dielectric filler 368. In one embodimentof the invention illustrated in FIG. 15 field spreader 380 is a regionhaving a dielectric constant which is in the range of approximately 1 to15. In one embodiment of the invention illustrated in FIG. 17, a fieldspreader may be comprised of a notch 384 in dielectric filler 368. Inone embodiment of the invention illustrated in FIG. 17, notch 384 is acone shaped notch in dielectric filler 368. In one embodiment of theinvention illustrated in FIG. 17, notch 384 is connected to coolingchamber 360 such that cooling fluid 361 in cooling chamber 360 at leastpartially fills notch 384. In one embodiment of the inventionillustrated in FIG. 17, notch 384 is connected to cooling chamber 360such that cooling fluid 361 in cooling chamber 360 fills notch 384.

In one embodiment of the invention illustrated in FIG. 18 field spreader382 is integrated into or protrudes from cooling plate 340. In oneembodiment of the invention illustrated in FIG. 18 field spreader 382 isintegrated into or protrudes from cooling plate 340 at tissue interface336. In one embodiment of the invention illustrated in FIG. 18 fieldspreader 382 is integrated into or protrudes from cooling plate 340 intotissue chamber 338. In one embodiment of the invention illustrated inFIG. 18 field spreader 382 may form at least a portion of tissueinterface 336.

In the embodiment of the invention illustrated in FIG. 19 skin 1307 isengaged in tissue chamber 338. In the embodiment of the inventionillustrated in FIG. 19 dermis 1305 and hypodermis 1303 are engaged intissue chamber 338. In the embodiment of the invention illustrated inFIG. 19, skin surface 1306 is engaged in tissue chamber 338 such thatskin surface 1306 is in contact with at least a portion of chamber wall354 and cooling plate 340. In the embodiment of the inventionillustrated in FIG. 19, skin surface 1306 is engaged in tissue chamber338 such that skin surface 1306 is in contact with at least a portion oftissue interface 336. As illustrated in FIG. 19, a vacuum pressure maybe used to elevate dermis 1305 and hypodermis 1303, separating dermis1305 and hypodermis 1303 from muscle 1301. As illustrated in FIG. 19, avacuum pressure may be used to elevate dermis 1305 and hypodermis 1303,separating dermis 1305 and hypodermis 1303 from muscle 1301 to, forexample, protect muscle 1301 by limiting or eliminating theelectromagnetic energy which reaches muscle 1301.

FIG. 20 is a cutaway view of a tissue head and antenna with tissueengaged according to one embodiment of the invention. In the embodimentof the invention illustrated in FIG. 20 applicator 320 includesapplicator housing 356, antenna 358, vacuum channels 350 and tissue head362. In the embodiment of the invention illustrated in FIG. 20 tissuehead 362 includes vacuum conduit 373, cooling elements 386 and coolingplate 340. In embodiments of the invention, cooling elements 386 may be,for example: solid coolants; heat sinks; liquid spray, gaseous spray,cooling plates, thermo-electric coolers; or and combinations thereof. Inthe embodiment of the invention illustrated in FIG. 20 vacuum channels350 are connected to vacuum conduit 373 and vacuum port 342. In theembodiment of the invention illustrated in FIG. 20 skin surface 1306 isengaged in tissue chamber 338 by, for example a vacuum pressure atvacuum ports 342, such that skin surface 1306 is in contact with atleast a portion of chamber wall 354 and cooling plate 340. In theembodiment of the invention illustrated in FIG. 20 skin surface 1306 isengaged in tissue chamber 338 by, for example a vacuum pressure atvacuum ports 342, such that skin surface 1306 is in contact with atleast a portion of tissue interface 336. As illustrated in FIG. 20, avacuum pressure at vacuum ports 342 may be used to elevate dermis 1305and hypodermis 1303, separating dermis 1305 and hypodermis 1303 frommuscle 1301. As illustrated in FIG. 20, a vacuum pressure at vacuumports 342 may be used to elevate dermis 1305 and hypodermis 1303,separating dermis 1305 and hypodermis 1303 from muscle 1301 to, forexample, protect muscle 1301 by limiting or eliminating theelectromagnetic energy which reaches muscle 1301.

FIGS. 21 through 23 illustrate tissue heads including a plurality ofwaveguide antennas according to one embodiment of the invention. In theembodiments of the invention illustrated in FIGS. 21 through 23 a tissuehead 362 includes a plurality of waveguide antennas 364 according toembodiments of the invention. In the embodiment of the inventionillustrated in FIG. 21, two waveguide antennas 364 are positioned intissue head 362. In the embodiment of the invention illustrated in FIG.22, four waveguide antennas 364 are positioned in tissue head 362. Inthe embodiment of the invention illustrated in FIG. 23, six waveguideantennas 364 are positioned in tissue head 362. In the embodiment of theinvention illustrated in FIGS. 21 through 23 waveguides 364 include feedconnectors 388 and tuning screws 390.

FIG. 24 illustrates a disposable tissue head 363 for use with anapplicator 320 according to one embodiment of the invention. Inembodiments of the invention disposable tissue head 363 may have all ofthe elements of tissue head 362. In embodiments of the inventiondisposable tissue head 363 may include elements of tissue head 362, suchas, for example, tissue interface 336, cooling plate 340, tissue chamber338, or vacuum ports 342. In embodiments of the invention disposabletissue head 363 may include a cooling chamber 360. In embodiments of theinvention disposable tissue head 363 may include a standoff 376. In theembodiment of the invention illustrated in FIG. 24 disposable tissuehead 363 engages with applicator housing 356, positioning antennas 364in disposable tissue head 363. FIG. 25 illustrates a disposable tissuehead 363 for use with an applicator 320 according to one embodiment ofthe invention. In the embodiment of the invention illustrated in FIG. 25disposable tissue head 363 engages with applicator housing 356 and isheld in place with latches 365.

Tissue Profiles

FIGS. 26 through 51 illustrate a series of profiles, including, forexample, profiles of power deposition, profiles of power loss density,profiles of specific absorption rates or profiles of tissue temperature,according to embodiments of the invention. In embodiments of the presentinvention, profiles such as for example, profiles of power deposition,profiles of power loss density, profiles of specific absorption rates orprofiles of tissue temperature may be referred to as tissue profiles. Inthe embodiments of the invention illustrated in FIGS. 26 through 51 theillustrated tissue profiles may be representative of, for example, SARprofiles, power loss density profiles or temperature profiles. In someembodiments of the invention, the embodiments and components ofembodiments of systems illustrated in FIGS. 2 through 25 as well as,e.g., those illustrated and described at FIGS. 3-7C and pp. 8-13 of U.S.Provisional App. No. 60/912,899; and FIGS. 3-9 and 20-26 and pp. 34-48and FIGS. 20-26 of U.S. Provisional App. No. 61/013,274 bothincorporated by reference in their entireties, as well as illustratedand described in, e.g., FIGS. 3A-7C and pp. 16-20 of Appendix 1 andFIGS. 20-26 and pp. 38-46 of Appendix 2 may be used to generate thetissue profiles illustrated in FIGS. 26 through 51.

FIGS. 26 through 35 illustrate a series of tissue profiles according toembodiments of the invention. In embodiments of the inventionillustrated in FIGS. 26 through 35 antenna 358 may be, for example, asimple dipole antenna or a waveguide antenna. In embodiments of theinvention illustrated in FIGS. 26 through 35 antenna 358 may bepositioned in a medium 1318. In embodiments of the invention illustratedin FIGS. 26 through 35 antenna 358 radiates an electromagnetic signalthrough medium 1318 and into tissue, generating the patterns illustratedin FIGS. 26 through 35. In one embodiment of the invention, medium 1318may be, for example, a dielectric material having a dielectric constant(which may also be referred to as permittivity) of approximately 10.

In the embodiment of the invention illustrated in FIG. 26 antenna 358may radiate energy at a frequency of, for example, approximately 3.0GHz. In the embodiment of the invention illustrated in FIG. 27 antenna358 may radiate energy at a frequency of, for example, approximately 3.5GHz. In the embodiment of the invention illustrated in FIG. 28 antenna358 may radiate energy at a frequency of, for example, approximately 4.0GHz. In the embodiment of the invention illustrated in FIG. 29 antenna358 may radiate energy at a frequency of, for example, approximately 4.5GHz. In the embodiment of the invention illustrated in FIG. 30 antenna358 may radiate energy at a frequency of, for example, approximately 5.0GHz. In the embodiment of the invention illustrated in FIG. 31 antenna358 may radiate energy at a frequency of, for example, approximately 5.8GHz. In the embodiment of the invention illustrated in FIG. 32 antenna358 may radiate energy at a frequency of, for example, approximately 6.5GHz. In the embodiment of the invention illustrated in FIG. 33 antenna358 may radiate energy at a frequency of, for example, approximately 7.5GHz. In the embodiment of the invention illustrated in FIG. 34 antenna358 may radiate energy at a frequency of, for example, approximately 8.5GHz. In the embodiment of the invention illustrated in FIG. 35 antenna358 may radiate energy at a frequency of, for example, approximately 9.0GHz. In one embodiment of the invention, a tissue profile, such as theprofile illustrated in FIGS. 34 and 35 may include at least twoconstructive interference peaks, where in a first constructiveinterference peak is positioned in tissue below a second constructiveinterference peak. In one embodiment of the invention, a tissue profile,such as the profile illustrated in FIGS. 34 and 35 may include at leasttwo constructive interference peaks, where in a second constructiveinterference peak is positioned near a skin surface.

In embodiments of the invention, wherein antenna 358 is representativeof a wave guide antenna such as, for example, the waveguide antennaillustrated in FIG. 48 radiating through, for example, at least aportion of a tissue head including a tissue interface, the frequenciesat which particular tissue profiles, such as, for example, SAR profiles,power loss profiles or temperature profiles are created may vary fromthe frequencies at which that such profiles are generated by a dipoleantenna. In one embodiment of the invention, a tissue head positionedbetween a waveguide antenna and a skin surface may comprise, forexample, for example, a standoff 376, a cooling chamber 360 filled withcooling fluid 361, such as, for example de-ionized water and a coolingplate 340. In one embodiment of the invention, wherein antenna 358 is awaveguide, antenna 358 may be positioned a distance of approximately 1.5millimeters from skin surface 1306. In one embodiment of the invention,FIG. 34 illustrates a resulting profile where antenna 358 is a waveguideantenna radiating energy through a tissue head at a frequency of, forexample, approximately 10 GHz. In one embodiment of the invention, FIG.35 illustrates a resulting profile where antenna 358 is a waveguideantenna radiating energy through a tissue head at a frequency of, forexample, approximately 12 GHz.

In embodiments of the invention illustrated in FIGS. 26 through 35,antenna 358 may be a dipole antenna and may have a length of, forexample, approximately one half wavelength (measured at the operationalfrequency). In embodiments of the invention illustrated in FIGS. 26through 35, antenna 358 may be positioned in, for example, a radiatingnear field region with respect to skin surface 1306. In embodiments ofthe invention illustrated in FIGS. 26 through 35 antenna 358 may bepositioned at a distance of, for example, approximately 10 millimetersfrom skin surface 1306. In embodiments of the invention illustrated inFIGS. 26 through 30 antenna 358 may be a dipole antenna having anantenna height of, for example, approximately 12 millimeters. In oneembodiment of the invention illustrated in FIG. 31 antenna 358 may be adipole antenna having an antenna height of, for example, approximately8.5 millimeters. In embodiments of the invention illustrated in FIGS. 32through 35 antenna 358 may be a dipole antenna having an antenna heightof, for example, approximately 7 millimeters.

In embodiments of the invention illustrated in FIGS. 26 through 35 powerfrom antenna 358 is transmitted through skin surface 1306, generating aprofile, such as, for example, a SAR profile, a power loss densityprofile or a temperature profile, in, for example, dermis 1305. Inembodiments of the invention illustrated in FIGS. 26 through 35 powertransmitted from antenna 358 though skin surface 1306 generates aprofile having a peak in first tissue region 1309. In embodiments of theinvention illustrated in FIGS. 26 through 35 power transmitted fromantenna 358 though skin surface 1306 generates a profile wherein themagnitude decreases from first tissue region 1309 to second tissueregion 1311. In embodiments of the invention illustrated in FIGS. 26through 35 power transmitted from antenna 358 though skin surface 1306generates a profile wherein the magnitude decreases from second tissueregion 1311 to third tissue region 1313. In embodiments of the inventionillustrated in FIGS. 26 through 35 power transmitted from antenna 358though skin surface 1306 generates a profile wherein the magnitudedecreases from third tissue region 1313 to fourth tissue region 1315.

In one embodiment of the invention, illustrated in, for example, FIGS.26 through 39, power transmitted from antenna 358 through skin surface1306 is at least partially reflected off of interface 1308 such that apeak magnitude of, for example, SAR, power loss density or temperature,is generated in first tissue region 1309 below skin surface 1306. In theembodiment of the invention illustrated in FIG. 26 through 39, interface1308 may be idealized as a substantially straight line for the purposeof simplified illustration, however, in actual tissue, interface 1308may be expected to be a non-linear, non-continuous, rough interfacewhich may also include tissue structures and groups of tissue structureswhich cross and interrupt interface 1308. In one embodiment of theinvention, a peak magnitude of, for example, SAR, power loss density ortemperature is formed as a result of constructive interference betweenincident and reflected power. In one embodiment of the invention, a peakmagnitude of, for example, SAR, power loss density or temperature formedas a result of constructive interference between incident and reflectedpower is positioned at first tissue region 1309 below a first layer ofdermal tissue. In one embodiment of the invention, a minimum magnitudeof, for example, SAR, power loss density or temperature is formed as aresult of destructive interference between incident and reflected power.In one embodiment of the invention, a minimum magnitude of, for example,SAR, power loss density or temperature formed as a result of destructiveinterference between incident and reflected power is positioned in afirst layer of dermal tissue near skin surface 1306. In one embodimentof the invention, interface 1308 may be, for example, an interfacebetween dermis 1305 and hypodermis 1303. In one embodiment of theinvention, first tissue region 1309 may be formed in the lower half ofthe dermis. In one embodiment of the invention, interface 1308 may be,for example, an interface between a high dielectric, high conductivitytissue layer and a low dielectric, low conductivity tissue layer. In oneembodiment of the invention, interface 1308 may be, for example, aninterface between a high dielectric, high conductivity tissue layer anda low dielectric tissue layer. In one embodiment of the invention,interface 1308 may be, for example, an interface between a glandularlayer and a layer of the hypodermis.

In one embodiment of the invention, energy transmitted through skinsurface 1306 creates a peak temperature in first region 1309. In oneembodiment of the invention, energy transmitted through skin surface1306 raises a temperature in first region 1309 to a temperaturesufficient to induce hyperthermia in tissue in region 1309. In oneembodiment of the invention, energy transmitted through skin surface1306 raises a temperature in first region 1309 to a temperaturesufficient to ablate tissue in region 1309. In one embodiment of theinvention, energy transmitted through skin surface 1306 raises atemperature in first region 1309 to a temperature sufficient to causecell death in tissue in region 1309. In one embodiment of the invention,energy transmitted through skin surface 1306 raises a temperature infirst region 1309 to a temperature sufficient to form a lesion core infirst region 1309. In one embodiment of the invention, energytransmitted through skin surface 1306 raises a temperature in firstregion 1309 to a temperature sufficient to create a lesion in tissue inregion 1309. In one embodiment of the invention, energy transmittedthrough skin surface 1306 raises the temperature of tissue in region1309 by dielectric heating. In one embodiment of the invention, energytransmitted through skin surface 1306 preferentially raises thetemperature of tissue in region 1309 above the temperature ofsurrounding regions. In one embodiment of the invention, energytransmitted through skin surface 1306 preferentially raises thetemperature of tissue in region 1309 above the temperature ofsurrounding regions to a temperature sufficient to cause secondaryeffects, such as, for example the destruction of bacteria in suchsurrounding regions.

In one embodiment of the invention, energy transmitted through skinsurface 1306 generates a temperature in first region 1309 sufficient toheat tissue around first region 1309, by, for example, thermalconductive heating. In one embodiment of the invention, energytransmitted through skin surface 1306 generates a temperature in firstregion 1309 sufficient to heat tissue structures, such as, for example,sweat glands or hair follicles, in tissue around first region 1309, by,for example, thermal conductive heating. In one embodiment of theinvention, energy transmitted through skin surface 1306 generates atemperature in first region 1309 sufficient to cause hyperthermia intissue around first region 1309, by, for example, thermal conductiveheating. In one embodiment of the invention, energy transmitted throughskin surface 1306 generates a temperature in first region 1309sufficient to ablate tissue around first region 1309, by, for example,thermal conductive heating. In one embodiment of the invention, energytransmitted through skin surface 1306 generates a temperature in firstregion 1309 sufficient to kill bacteria in tissue or tissue structuresaround first region 1309, by, for example, thermal conductive heating.In one embodiment of the invention, energy transmitted through skinsurface 1306 generates a temperature in first region 1309 sufficient tocreate a lesion in tissue around first region 1309, by, for example,thermal conductive heating. In one embodiment of the invention, energytransmitted through skin surface 1306 generates a temperature in firstregion 1309 sufficient to expand a lesion into tissue around firstregion 1309, by, for example, thermal conductive heating.

Near Field

FIGS. 36 through 39 illustrate a series of tissue profiles according toone embodiment of the invention. In the embodiment of the inventionillustrated in FIGS. 36 through 39 antenna 358 may be, for example, asimple dipole antenna or a waveguide antenna. In the embodiment of theinvention illustrated in FIG. 36 through 39 antenna 358 may be excitedat a predetermined frequencies such as, for example, approximately 5.8GHz. In embodiments of the invention illustrated in FIGS. 36 through 38,antenna 358 may be positioned in, for example, a radiating near fieldregion with respect to skin surface 1306. In an embodiment of theinvention illustrated in FIG. 39, antenna 358 may be positioned in, forexample, a reactive near field region with respect to skin surface 1306.In embodiments of the invention illustrated in FIGS. 36 through 39antenna 358 may be positioned at a distance A of, for example, betweenapproximately 10 millimeters and approximately 2 millimeters from skinsurface 1306. In embodiments of the invention illustrated in FIGS. 36through 39 antenna 358 may be positioned in a medium 1318. Inembodiments of the invention illustrated in FIGS. 36 through 39 antenna358 may be a dipole antenna having an antenna height of approximately8.5 millimeters. In the embodiments of the invention illustrated inFIGS. 36 through 39 antenna 358 may radiate energy at a frequency of,for example, approximately 5.8 GHz.

In embodiments of the invention illustrated in FIGS. 36 through 39 powerfrom antenna 358 is transmitted through skin surface 1306, generating atissue profile in dermis 1305. In embodiments of the inventionillustrated in FIGS. 36 through 39 power transmitted from antenna 358though skin surface 1306 generates a tissue profile having a peak infirst tissue region 1309. In embodiments of the invention illustrated inFIGS. 36 through 39 power transmitted from antenna 358 though skinsurface 1306 generates a tissue profile which may represent, forexample, SAR, power loss density or temperature. In embodiments of theinvention illustrated in FIGS. 36 through 39 power transmitted fromantenna 358 though skin surface 1306 generates a tissue profile whereinthe magnitude of, for example, SAR, power loss density or temperature,decreases from first tissue region 1309 to second tissue region 1311,from second tissue region 1311 to third tissue region 1313 and fromthird tissue region 1313 to fourth tissue region 1315.

In one embodiment of the invention, illustrated in, for example, FIG.36, power transmitted from antenna 358 through skin surface 1306 is atleast partially reflected off of interface 1308 such that a peak of, forexample, SAR, power loss density or temperature, is generated in firsttissue region 1309 below skin surface 1306. In one embodiment of theinvention illustrated in, for example, FIG. 36, a peak of, for example,SAR, power loss density or temperature formed as a result ofconstructive interference between incident and reflected power ispositioned at first tissue region 1309 below a first layer of dermaltissue. In one embodiment of the invention illustrated in, for example,FIG. 36, a peak of, for example, SAR, power loss density or temperatureformed as a result of constructive interference between incident andreflected power is positioned at first tissue region 1309 in a lowerhalf of dermis 1305. In one embodiment of the invention illustrated inFIG. 36 antenna 358 may be positioned at a distance A of, for example,approximately 10 millimeters from skin surface 1306. In one embodimentof the invention illustrated in FIG. 37 antenna 358 may be positioned ata distance A of, for example, approximately 5 millimeters from skinsurface 1306. In one embodiment of the invention illustrated in FIG. 38antenna 358 may be positioned at a distance A of, for example,approximately 3 millimeters from skin surface 1306. In one embodiment ofthe invention illustrated in FIG. 39 antenna 358 may be positioned at adistance A of, for example, approximately 2 millimeters from skinsurface 1306. In one embodiment of the invention illustrated in FIGS. 36through 38, tissue in region 1309 is preferentially heated with respectto tissue in layers above first tissue region 1309.

In one embodiment of the invention illustrated in FIG. 36 antenna 358may be positioned at a distance A within a radiating near field of skinsurface 1306. In one embodiment of the invention illustrated in FIG. 37antenna 358 may be positioned at a distance A within a radiating nearfield of skin surface 1306. In one embodiment of the inventionillustrated in FIG. 38 antenna 358 may be positioned at a distance Awithin a radiating near field of skin surface 1306. In one embodiment ofthe invention illustrated in FIG. 39 antenna 358 may be positioned at adistance A within a reactive near field of skin surface 1306. Asillustrated in FIG. 39, in one embodiment of the invention, positioningan antenna in a reactive near field results in substantial reactivecoupling, which increases power deposition at the upper skin layer anddestroys the preferential heating profiles illustrated in FIGS. 36thorough 38. In one embodiment of the invention, a reactive near fieldmay be that distance which results in substantial reactive couplingbetween an antenna and adjacent tissue, increasing power deposition atthe upper skin layer and destroying the preferential heating profilesillustrated in FIGS. 36 thorough 38

Preferential Heating—Dermis

FIGS. 40 through 43 illustrate tissue profiles according to oneembodiment of the invention. In embodiments of the invention illustratedin FIGS. 40 through 43 dermis 1305 and hypodermis 1303 may containtissue structures 1325 which may be, for example, sweat glands,including, for example, eccrine glands, apocrine glands or apoeccrineglands. In embodiments of the invention illustrated in FIGS. 40 through43 dermis 1305 and hypodermis 1303 may contain tissue structures 1325which may be, for example, sweat glands, including, for example, eccrineglands, apocrine glands or apoeccrine glands. In embodiments of theinvention illustrated in FIGS. 40 through 43 dermis 1305 and hypodermis1303 may contain tissue structures 1325 which may be, for example, hairfollicles. In embodiments of the invention illustrated in FIGS. 40through 43 tissue structures 1325 may include ducts 1329 extending fromtissue structures 1325 to skin surface 1306. In embodiments of theinvention, tissue structures 1325 include groups of tissue structures1325.

FIG. 40 illustrates a tissue profile according to one embodiment of theinvention. In the embodiment of the invention illustrated in FIG. 40 alesion core 1321 is created in a predetermined portion of dermis 1305by, for example, irradiating dermis 1305 with electromagnetic radiationto generate dielectric heating in tissue at lesion core 1321. In oneembodiment of the invention, lesion core 1321 may be, for example, apoint or region within a tissue layer where a lesion starts to grow. Inthe embodiment of the invention illustrated in FIG. 40 lesion core 1321is created by heat generated in dermal tissue by dielectric heating oflesion core 1321. In the embodiment of the invention illustrated in FIG.40 lesion core 1321 expands as energy is added to dermis 1305. In theembodiment of the invention illustrated in FIG. 40 lesion core 1321 maybe located in a region of dermis 1305 where a constructive interferencepeak is generated by electromagnetic energy transmitted through skinsurface 1306. In the embodiment of the invention illustrated in FIG. 40lesion core 1321 may be located in a region of dermis 1305 where aconstructive interference peak is generated by electromagnetic energytransmitted through skin surface 1306 wherein at least a portion of theelectromagnetic energy transmitted through skin surface 1306 reflectsoff of interface 1308 which may be, for example, an interface betweenhigh dielectric, high conductivity tissue and low dielectric, lowconductivity tissue. In the embodiment of the invention illustrated inFIG. 40 lesion core 1321 may be located in a region of dermis 1305 wherea constructive interference peak is generated by electromagnetic energytransmitted through skin surface 1306 wherein at least a portion of theelectromagnetic energy transmitted through skin surface 1306 reflectsoff of interface 1308 which may be, for example, an interface betweenhigh dielectric, high conductivity tissue and low dielectric tissue. Inthe embodiment of the invention illustrated in FIG. 40 interface 1308may be idealized as a substantially straight line for the purpose ofsimplified illustration, however, in actual tissue, interface 1308 maybe a non-linear, non-continuous, rough interface which may also includemany tissue structures and groups of tissue structures which cross andinterrupt the tissue interface. In the embodiment of the inventionillustrated in FIG. 40 lesion core 1321 may be located in a region ofdermis 1305 where a constructive interference peak is generated byelectromagnetic energy transmitted through skin surface 1306 wherein atleast a portion of the electromagnetic energy transmitted through skinsurface 1306 reflects off of interface 1308 which may be, for example,an interface between dermis 1305 and hypodermis 1303.

FIG. 41 illustrates a tissue profile according to one embodiment of theinvention. In the embodiment of the invention illustrated in FIG. 41lesion core 1321 expands as energy is added to dermis 1305, generatingheat which is conducted into surrounding tissue creating expanded lesion1323. In the embodiment of the invention illustrated in FIG. 41 heatconducted from lesion core 1321 into expanded lesion 1323 damagestissue, including tissue structures 1325 outside lesion 1321. In theembodiment of the invention illustrated in FIG. 41 heat conducted fromlesion core 1321 into expanded lesion 1323 crosses interface 1308 anddamages tissue below interface 1308, including tissue structures 1325outside and below lesion core 1321.

FIG. 42 illustrates a tissue profile according to one embodiment of theinvention. In the embodiment of the invention illustrated in FIG. 42 alesion core 1321 is created in a predetermined portion of dermis 1305by, for example, irradiating dermis 1305 with electromagnetic radiationto generate dielectric heating in tissue at lesion core 1321. In theembodiment of the invention illustrated in FIG. 42 lesion core 1321expands as energy is added to dermis 1305. In the embodiment of theinvention illustrated in FIG. 42 heat is removed from skin surface 1306.In the embodiment of the invention illustrated in FIG. 42 heat isremoved from dermis 1305 through skin surface 1306. In the embodiment ofthe invention illustrated in FIG. 42 heat is removed from dermis 1305through skin surface 1306 by cooling skin surface 1306. In theembodiment of the invention illustrated in FIG. 42 heat removed fromdermis 1305 through skin surface 1306 prevents lesion core 1321 andexpanded lesion 1323 from growing in the direction of skin surface 1306.In the embodiment of the invention illustrated in FIG. 42 removed fromdermis 1305 through skin surface 1306 prevents lesion core 1321 andexpanded lesion 1323 from growing into cooled region 1327.

FIG. 43 illustrates a tissue profile according to one embodiment of theinvention. In the embodiment of the invention illustrated in FIG. 43 alesion core 1321 is created in a predetermined portion of dermis 1305by, for example, irradiating dermis 1305 with electromagnetic radiationto generate dielectric heating in tissue at lesion core 1321 andexpanded lesion 1323 is created by heat conducted from lesion core 1321.In the embodiment of the invention illustrated in FIG. 43 lesion core1321 expands as energy is added to dermis 1305 and expanded lesion 1323expands as heat is conducted from lesion core 1321. In the embodiment ofthe invention illustrated in FIG. 43 heat is removed from skin surface1306. In the embodiment of the invention illustrated in FIG. 43 heat isremoved from dermis 1305 through skin surface 1306. In the embodiment ofthe invention illustrated in FIG. 43 heat is removed from dermis 1305through skin surface 1306 by cooling skin surface 1306. In theembodiment of the invention illustrated in FIG. 43 heat removed fromdermis 1305 through skin surface 1306 prevents lesion core 1321 andexpanded lesion 1323 from growing in the direction of skin surface 1306.In the embodiment of the invention illustrated in FIG. 43 removed fromdermis 1305 through skin surface 1306 prevents lesion core 1321 andexpanded lesion 1323 from growing into cooled region 1327.

Preferential Heating—Glandular Layer

FIGS. 44 through 47 illustrate tissue profiles according to embodimentsof the invention. In embodiments of the invention illustrated in FIGS.44 through 47 dermis 1305 and hypodermis 1303 may contain tissuestructures 1325 which may be, for example, sweat glands, including, forexample, eccrine glands, apocrine glands or apoeccrine glands. Inembodiments of the invention illustrated in FIGS. 44 through 47 dermis1305 and hypodermis 1303 may contain tissue structures 1325 which maybe, for example, sweat glands, including, for example, eccrine glands,apocrine glands or apoeccrine glands. In embodiments of the inventionillustrated in FIGS. 44 through 47 dermis 1305 and hypodermis 1303 maycontain tissue structures 1325 which may be, for example, hairfollicles. In embodiments of the invention illustrated in FIGS. 44through 47 tissue structures 1325 may include ducts 1329 extending fromtissue structures 1325 to skin surface 1306. In embodiments of theinvention illustrated in FIGS. 44 through 47 tissue structures 1325 maybe concentrated in a glandular layer 1331. In embodiments of theinvention illustrated in FIGS. 44 through 47 tissue structures 1325 maybe concentrated in a glandular layer 1331 wherein glandular layer 1331has an upper interface 1335 and a lower interface 1333. In embodimentsof the invention illustrated in FIGS. 44 through 47 glandular layer 1331may have an upper interface 1335 between glandular layer 1331 and dermis1305. In embodiments of the invention illustrated in FIGS. 44 through 47glandular layer 1331 may have a lower interface 1333 between glandularlayer 1331 and hypodermis 1303. In the embodiment of the inventionillustrated in FIGS. 44 through 47 interface 1333 may be, in actualtissue a non-linear, non-continuous, rough interface which may alsoinclude many tissue structures and groups of tissue structures andgroups of tissue structures which add to the roughness and nonlinearityof tissue interface 1333.

In embodiments of the invention illustrated in FIGS. 44 through 47tissue structures 1325 may be composed, at least in part of highdielectric/high conductivity tissue such as, for example, sweat glands.In embodiments of the invention illustrated in FIGS. 44 through 47tissue structures 1325 may be composed, at least in part of tissuehaving a high water content, such as, for example, sweat glands. Inembodiments of the invention illustrated in FIGS. 44 through 47glandular layer 1331 may be composed, at least in part of highdielectric/high conductivity tissue. In embodiments of the inventionillustrated in FIGS. 44 through 47 glandular layer 1331 may have anupper interface 1335 between glandular layer 1331 and highdielectric/high conductivity tissue, such as, for example, dermis 1305.In embodiments of the invention illustrated in FIGS. 44 through 47glandular layer 1331 may have a lower interface 1333 between glandularlayer 1331 and low dielectric/low conductivity tissue, such as, forexample, hypodermis 1303. In embodiments of the invention illustrated inFIGS. 44 through 47 glandular layer 1331 may have a lower interface 1333between glandular layer 1331 and low dielectric tissue.

FIG. 44 illustrates a tissue profile according to one embodiment of theinvention. In the embodiment of the invention illustrated in FIG. 44 alesion core 1321 is created in a predetermined portion of glandularlayer 1331 by, for example, irradiating glandular layer 1331 withelectromagnetic radiation to generate dielectric heating in tissue atlesion core 1321. In the embodiment of the invention illustrated in FIG.44 lesion core 1321 is created by heat generated in glandular layer 1331by dielectric heating of lesion core 1321. In the embodiment of theinvention illustrated in FIG. 44 lesion core 1321 expands as energy isadded to glandular layer 1331. In the embodiment of the inventionillustrated in FIG. 44 lesion core 1321 may be located in a region ofglandular layer 1331 where a constructive interference peak of, forexample, SAR, power loss density or temperature, is generated byelectromagnetic energy transmitted through skin surface 1306. In theembodiment of the invention illustrated in FIG. 44 lesion core 1321 maybe located in a region of glandular layer 1331 where a constructiveinterference peak of, for example, SAR, power loss density ortemperature, is generated by electromagnetic energy transmitted throughskin surface 1306 wherein at least a portion of the electromagneticenergy transmitted through skin surface 1306 reflects off of lowerinterface 1333. In the embodiment of the invention illustrated in FIG.44 lesion core 1321 may be located in a region of glandular layer 1331where a constructive interference peak of, for example, SAR, power lossdensity or temperature, is generated by electromagnetic energytransmitted through skin surface 1306 wherein at least a portion of theelectromagnetic energy transmitted through skin surface 1306 reflectsoff of lower interface 1333 which may be, for example, an interfacebetween glandular layer 1331 and hypodermis 1303.

FIG. 45 illustrates a tissue profile according to one embodiment of theinvention. In the embodiment of the invention illustrated in FIG. 45lesion core 1321 expands as energy is added to glandular layer 1331,generating heat which is conducted into surrounding tissue, creatingexpanded lesion 1323. In the embodiment of the invention illustrated inFIG. 45 heat conducted from lesion core 1321 into expanded lesion 1323damages tissue, including tissue structures 1325 outside lesion core1321. In the embodiment of the invention illustrated in FIG. 45 heatconducted from lesion core 1321 into expanded lesion 1323 crosses lowerinterface 1333 and damages tissue below lower interface 1333 and outsidelesion core 1321.

FIGS. 46 and 47 illustrate tissue profiles according to one embodimentof the invention. In the embodiment of the invention illustrated inFIGS. 46 and 47 a lesion core 1321 is created in a portion of glandularlayer 1331 by, for example, irradiating glandular layer 1331 withelectromagnetic radiation to generate dielectric heating in tissue atlesion core 1321. In the embodiments of the invention illustrated inFIGS. 46 and 47 lesion core 1321 expands as energy is added to glandularlayer 1331 and expanded lesion 1323 is created by heat conducted fromlesion core 1323. In the embodiments of the invention illustrated inFIGS. 46 and 47 heat is removed from skin surface 1306. In theembodiments of the invention illustrated in FIGS. 46 and 47 heat isremoved from dermal layer 1305 through skin surface 1306. In theembodiments of the invention illustrated in FIGS. 46 and 47 heat isremoved from dermal layer 1305 through skin surface 1306 by cooling skinsurface 1306, creating cooled region 1307 in dermis 1305. In theembodiment of the invention illustrated in FIG. 47 heat removed fromdermal layer 1305 through skin surface 1306 prevents expanded lesion1323 from growing in the direction of skin surface 1306. In theembodiment of the invention illustrated in FIG. 46 heat removed fromglandular layer 1331 through skin surface 1306 prevents expanded lesion1323 from growing into cooled region 1327.

FIGS. 48 through 51 illustrate tissue profiles and apparatuses accordingto embodiments of the invention. In FIGS. 48 through 51, antenna 358 maybe, for example, waveguide antenna 364. In the embodiment of theinvention illustrated in FIGS. 48 and 49, waveguide antenna 364 mayinclude, for example, waveguide tubing 366 and dielectric filler 368. Inthe embodiment of the invention illustrated in FIGS. 48 and 49electromagnetic energy may be radiated into dermis 1305 through a tissuehead 362 which may include, for example, standoff 376, coolant chamber360 and cooling plate 340. In the embodiment of the inventionillustrated in FIG. 48 a peak which may be, for example, a peak SAR,peak power loss density or peak temperature, is generated in firsttissue region 1309. In the embodiment of the invention illustrated inFIG. 48 a reduced magnitude which may be, for example, a reduced SAR,reduced power loss density or reduced temperature, is generated insecond tissue region 1311 with further reduced magnitudes in thirdtissue region 1313 and fourth tissue region 1315. In the embodiment ofthe invention illustrated in FIG. 48 dermis 1305 is separated fromhypodermis 1303 by interface 1308. In the embodiment of the inventionillustrated in FIG. 48 interface 1308 may be idealized as asubstantially straight line for the purposes of simplified illustration,however, in actual tissue, interface 1308 may be a non-linear,non-continuous, rough interface which may also include many tissuestructures and groups of tissue structures which cross and interrupt thetissue interface. In the embodiment of the invention illustrated in FIG.48 hypodermis 1303 lies over muscle tissue 1301. In the embodiment ofthe invention illustrated in FIG. 48 electromagnetic radiation may beradiated at a frequency of, for example, between 5 and 6.5 GHz. In theembodiment of the invention illustrated in FIG. 48 electromagneticradiation may be radiated at a frequency of, for example, approximately5.8 GHz. In the embodiment of the invention illustrated in FIG. 48dermis 1305 may be assumed have a dielectric constant of, for example,approximately 38 and a conductivity of, for example, approximately 4.5siemens per meter. In the embodiment of the invention illustrated inFIG. 48 hypodermis 1303 may be assumed to have a dielectric constant of,for example, approximately 5 and a conductivity of, for example,approximately 0.31 siemens per meter. In the embodiment of the inventionillustrated in FIG. 48 muscle tissue 1301 may be assumed to have adielectric constant of, for example, approximately 42 and a conductivityof, for example, approximately 5.2 siemens per meter. In the embodimentof the invention illustrated in FIG. 48 standoff 376 may be, forexample, polycarbonate and may have a dielectric constant of, forexample, approximately 3.4 and a conductivity of, for example,approximately 0.0051 siemens per meter. In the embodiment of theinvention illustrated in FIG. 48 cooling plate 340 may be, for example,alumina (99.5%) and may have a dielectric constant of, for example,approximately 9.9 and a conductivity of, for example, approximately3×10⁻⁴ siemens per meter. In the embodiment of the invention illustratedin FIG. 48 cooling fluid 361 may be, for example, de-ionized water andmay have, for example, a dielectric constant of, for example,approximately 81 and a conductivity of, for example, approximately0.0001 siemens per meter.

In the embodiment of the invention illustrated in FIG. 49 a peak, whichmay be, for example, a peak SAR, peak power loss density or peaktemperature, is generated in first tissue region 1309. In the embodimentof the invention illustrated in FIG. 48 a reduced magnitude which maybe, for example, a reduced SAR, reduced power loss density or reducedtemperature, is generated in second tissue region 1311 with furtherreduced magnitudes in third tissue region 1313 and fourth tissue region1315. In the embodiment of the invention illustrated in FIG. 49 dermis1305 is separated from hypodermis 1303 by interface 1308. In theembodiment of the invention illustrated in FIG. 49 interface 1308 may bemodeled as a nonlinear interface, to more closely resemble an actualinterface between dermal and hypodermal tissue. In the embodiment of theinvention illustrated in FIG. 49 hypodermis 1303 lies over muscle tissue1301. In the embodiment of the invention illustrated in FIG. 49electromagnetic radiation may be radiated at a frequency of, forexample, 5.8 GHz. In the embodiment of the invention illustrated in FIG.49 dermis 1305 may be assumed to have a dielectric constant of, forexample, 38.4 and a conductivity of, for example 4.54 siemens per meter.In the embodiment of the invention illustrated in FIG. 49 hypodermis1303 may be assumed to have, for example, a dielectric constant of, forexample, 4.9 and a conductivity of, for example, 0.31 siemens per meter.In the embodiment of the invention illustrated in FIG. 49 muscle tissue1301 may be assumed to have, for example, a dielectric constant of, forexample, 42.22 and a conductivity of, for example, 5.2 siemens permeter. In the embodiment of the invention illustrated in FIG. 49standoff 376 may be, for example, polycarbonate and may have, forexample, a dielectric constant of, for example, 3.4 and a conductivityof, for example, 0.0051 siemens per meter. In the embodiment of theinvention illustrated in FIG. 49 cooling plate 340 may be, for example,alumina (99.5%) and may have, for example, a dielectric constant of, forexample, 9.9 and a conductivity of, for example, 3×10⁻⁴ siemens permeter. In the embodiment of the invention illustrated in FIG. 49 coolingfluid 361 may be, for example, de-ionized water and may have, forexample, a dielectric constant of, for example, 81 and a conductivityof, for example, 0.0001 siemens per meter.

FIG. 50 illustrates a tissue profile according to one embodiment of theinvention. FIG. 51 illustrates a tissue profile according to oneembodiment of the invention. In the embodiment of the inventionillustrated in FIGS. 50 and 51, antenna 358 may be, for example, awaveguide antenna 364. In one embodiment of the invention, waveguideantenna 364 may have a dielectric filler 368. In one embodiment of theinvention, antenna 358 may be positioned on, for example, a tissue head362 comprising, for example, standoff 376, coolant chamber 360 andcooling plate 340. In one embodiment of the invention, cooling chamber340 may contain cooling fluid 361, which may be, for example de-ionizedwater. In one embodiment of the invention, a tissue head 362 may includea tissue chamber (not shown) adapted to position tissue against tissueinterface 336. In one embodiment of the invention, antenna 358 isadapted to transmit electromagnetic radiation through skin surface 1306creating a tissue profile which may be representative of, for example, aSAR profile, a power loss density profile or a temperature profile. Inone embodiment of the invention, the tissue profile includes firsttissue region 1309, second tissue region 1311, third tissue region 1313and fourth tissue region 1315. In one embodiment of the invention, firsttissue region 1309 may represent, for example, a peak SAR, peak powerloss density or peak temperature. In one embodiment of the invention,first tissue region 1309 may be located in, for example, dermis 1305,near an interface 1308 between dermis 1305 and hypodermis 1303, whichoverlies muscle 1301. In the embodiment of the invention illustrated inFIG. 51, field spreader 379 is located in coolant chamber 360. In theembodiment of the invention illustrated in FIG. 51, field spreader 379may be used to, for example, spread and flatten first tissue region1309. In the embodiment of the invention illustrated in FIG. 51 fieldspreader 379 may be used to, for example, spread and flatten lesionsformed in first tissue region 1309.

Further General Embodiments Procedure

In one embodiment of the invention, electromagnetic power is deliveredto the skin for a predetermined period of time. In one embodiment of theinvention skin is engaged in, for example, a tissue chamber prior to thedelivery of energy. In one embodiment of the invention, skin is cooledprior to the application of electromagnetic energy. In one embodiment ofthe invention, skin is cooled during the application of electromagneticenergy. In one embodiment of the invention, skin is cooled after theapplication of electromagnetic energy. In one embodiment of theinvention, energy is delivered to the skin by applying a predeterminedamount of power to an antenna positioned in close proximity, which mayalso be referred to as proximal, to the surface of the skin. In oneembodiment of the invention, skin is positioned in close proximity to anelectromagnetic energy device. In one embodiment of the invention, skinis positioned in close proximity to an electromagnetic energy deliverydevice using vacuum pressure to hold the skin in position. In oneembodiment of the invention a region to be treated is anesthetized priorto treatment. In one embodiment of the invention anesthesia in theanesthetized region may change the dielectric properties of the tissueto be treated. In one embodiment of the invention, characteristics ofthe electromagnetic radiation irradiated through the skin are modifiedto account for variables, such as, for example the dielectric propertiesof the anesthesia, which determine anesthesia's influence on thetreatment. Variables that may determine anesthesia's influence ontreatment may include, for example: time from administration;vasodilatation or vasoconstriction characteristics of anesthetic; volumeof anesthesia administered; anesthesia type (liquid injected, topical);location/depth in tissue anesthesia is administered; method ofadministration, such as, for example, one or multiple locations. In oneembodiment of the invention, a template may be used to align a handpieceadapted to deliver electromagnetic energy to tissue. In one embodimentof the invention, a template may be used to align a handpiece as thehandpiece is moved from position to position in, for example, theaxilla. In one embodiment of the invention, a template is used to alignan injection site for the delivery of, for example, anesthesia which maybe, for example, lidocaine. In one embodiment of the invention, atemplate is used to facilitate treatment by indicating regions whichhave been previously treated. In one embodiment of the invention, atemplate may be aligned by, for example, using henna, sharpie marks ortattoos.

Tissue Structure Regions

In one embodiment of the invention, tissue to be treated may be made upof layers having particular dielectric and conductivity characteristics.In one embodiment of the invention tissue having a high dielectricconstant, also referred to as high dielectric tissue, may have adielectric constant greater than approximately 25. In one embodiment ofthe invention tissue having a low dielectric constant, also referred toas low dielectric tissue, may have a dielectric constant less thanapproximately 10. In one embodiment of the invention tissue having ahigh conductivity, also referred to as high conductivity tissue, mayhave a conductivity greater than approximately 1.0 siemens per meter. Inone embodiment of the invention tissue having a low conductivity, alsoreferred to as high dielectric tissue, may have a conductivity of lessthan approximately 1.0 siemens per meter.

In one embodiment of the invention, low dielectric, low conductivitytissue may be, for example the hypodermis. In one embodiment of theinvention, low dielectric tissue, low conductivity tissue, such as, forexample, fat, may be tissue found in the hypodermis. In one embodimentof the invention, low dielectric, low conductivity tissue may be, forexample a layer of the hypodermis below a glandular layer. In oneembodiment of the invention, low dielectric tissue may be, for examplethe hypodermis. In one embodiment of the invention, low dielectrictissue, such as, for example, fat, may be tissue found in thehypodermis. In one embodiment of the invention, low dielectric tissuemay be, for example a layer of the hypodermis below a glandular layer.

In one embodiment of the invention, high dielectric, high conductivitytissue may be, for example tissue found in the dermis. In one embodimentof the invention, high dielectric, high conductivity tissue may be, forexample tissue found in the dermis. In one embodiment of the invention,high dielectric, high conductivity tissue may be, for example, tissuefound in a glandular layer. In one embodiment of the invention, highdielectric, high conductivity tissue may be, for example, muscle tissue.

Glandular Layer

In one embodiment of the invention, a glandular layer may be, forexample a layer of high dielectric, high conductivity tissue. In oneembodiment of the invention, a glandular layer may be a layer of tissuewith high water content. In one embodiment of the invention, a glandularlayer may be a tissue layer in the region of an interface between thedermis and hypodermis which contains sufficient glandular tissue toraise the dielectric constant and conductivity of the glandular layer toa magnitude sufficient to create a standing wave pattern having a peakE-field in the glandular layer. In one embodiment of the invention,glandular tissue may occupy an average thickness of three to fivemillimeters in a five millimeter thick piece of human skin. In oneembodiment of the invention, a glandular layer may include both apocrinegland lobules and eccrine gland lobules within the glandular layer. Inone embodiment of the invention, a glandular layer may be a layer in thehuman axilla where substantially all of the sweat glands are localized.In one embodiment of the invention, wherein a glandular layer includesboth apocrine and eccrine gland lobules, the apocrine gland modules maybe more numerous and larger than the eccrine gland lobules. In oneembodiment of the invention, a glandular layer may be a layer of tissuewhich includes a concentration of glands, such as, for example, eccrine,apoeccrine and/or apocrine sweat glands, sufficient to raise theconductivity of tissue surrounding the glands. In one embodiment of theinvention, a glandular layer may be a layer of tissue which includes aconcentration of glands, such as, for example, eccrine, apoeccrineand/or apocrine sweat glands, sufficient to raise the dielectricconstant of tissue surrounding the glands. In one embodiment of theinvention, a glandular layer may be a region of the hypodermis withsufficient glandular tissue to raise the dielectric constant of thatregion of the hypodermis to a magnitude sufficient to reduce oreliminate reflected electromagnetic radiation at the dermal, hypodermalinterface. In one embodiment of the invention, a glandular layer may bea region of the hypodermis with sufficient glandular tissue to raise thedielectric constant of that region of the hypodermis to a magnitudesufficient to reduce or eliminate reflected electromagnetic radiation atthe dermal, hypodermal interface, moving a standing wave into thehypodermis. In one embodiment of the invention, a glandular layer may bea region of the hypodermis with sufficient glandular tissue to raisedielectric constant to match the dielectric constant of the adjoiningdermis. In one embodiment of the invention, a glandular layer may be aregion of the hypodermis with sufficient glandular tissue to raisedielectric constant of the glandular layer to match the dielectricconstant of surrounding hypodermis. In one embodiment of the invention,a glandular layer may be a region of the hypodermis with sufficientglandular tissue to raise dielectric constant of the glandular layer toexceed the dielectric constant of surrounding hypodermis. In oneembodiment of the invention, a glandular layer may have a dielectricconstant of greater than approximately 20. In one embodiment of theinvention, a glandular layer may have a conductivity of greater thanapproximately 2.5 siemens per meter.

Interface

In one embodiment of the invention, a critical interface, which may alsobe referred to as a dielectric interface or a dielectric discontinuity,may be an interface between a layer of tissue having a high dielectricconstant and high conductivity and a layer of tissue having a lowdielectric constant. In one embodiment of the invention, a dielectricinterface may be an interface between a layer of tissue having a highdielectric constant and high conductivity and a layer of tissue having alow dielectric constant and low conductivity. In one embodiment of theinvention, a critical interface may exist at the interface between thedermis and a glandular layer. In one embodiment of the invention, acritical interface may be an interface between the dermis and thehypodermis. In one embodiment of the invention, a critical interface maybe an interface between the dermis and a portion of the hypodermis. Inone embodiment of the invention, a critical interface may be aninterface between the dermis and a portion of the hypodermis having alimited number of sweat glands. In one embodiment of the invention, acritical interface may be an interface between the dermis and a regionof the hypodermis which does not include a glandular region. In oneembodiment of the invention, a critical interface may be an interfacebetween the dermis and a region of the hypodermis which does not includea significant number of tissue structures.

Treatment

In embodiments of the invention, tissue to be treated may be treated by,for example, raising the temperature of the tissue. In embodiments ofthe invention, tissue to be treated may be treated by, for example,raising the temperature of the tissue to a temperature sufficient tocause a change in the tissue. In embodiments of the invention, tissue tobe treated may be treated by, for example, raising the temperature ofthe tissue to a temperature sufficient to damage the tissue. Inembodiments of the invention, tissue to be treated may be treated by,for example, raising the temperature of the tissue to a temperaturesufficient to destroy the tissue. In embodiments of the invention,electromagnetic radiation is used to heat tissue to create a lesionwhere the lesion starts as a result of damage from heat generated bydielectric heating of tissue and the lesion is enlarged at least in partas consequence of thermal conduction of heat generated by the dielectricheating. In embodiments of the invention electromagnetic radiation maybe used to heat the contents, such as, for example, sebum, of a tissuestructure, such as, for example a hair follicle. In embodiments of theinvention electromagnetic radiation may be used to heat the contents,such as, for example, sweat of a tissue structure, such as, for examplea hair follicle. In embodiments of the invention electromagneticradiation may be used to heat the contents, such as, for example, sebumof a tissue structure, such as, for example a hair follicle to atemperature sufficient to damage or destroy, for example, bacteria inthe contents. In one embodiment of the invention, electromagneticradiation may be used to heat tissue to a temperature sufficient tocause secondary effects in surrounding tissue or tissue structures, suchas, for example, heating bacteria in surrounding tissue or surroundingtissue structures. In one embodiment of the invention, electromagneticradiation may be used to heat tissue to a temperature sufficient tocause secondary effects in surrounding tissue or tissue structures, suchas, for example, killing bacteria in surrounding tissue or surroundingtissue structures.

Target Tissue

In embodiments of the invention tissue to be treated as, for example, byraising the temperature of the tissue, may be referred to as targettissue.

Tissue to be Treated Tissue Layers

In embodiments of the invention target tissue may be tissue adjacent toa dermal, hypodermal interface. In embodiments of the invention targettissue may be tissue in a dermal layer, in close proximity to a dermal,hypodermal interface. In embodiments of the invention target tissue maybe deep dermal tissue. In embodiments of the invention target tissue maybe tissue adjacent to a skin, fat interface. In embodiments of theinvention target tissue may be tissue adjacent to a critical interface.In embodiments of the invention target tissue may be tissue adjacent toan interface between a glandular layer and a low dielectric layer. Inembodiments of the invention target tissue may be tissue adjacent to aninterface between a glandular layer and a layer of the hypodermis.

Physical Structures

In embodiments of the invention target tissue may be axillary tissue. Inembodiments of the invention target tissue may be tissue in a hairbearing area. In embodiments of the invention target tissue may betissue located in a region having at least 30 sweat glands per squarecentimeter. In embodiments of the invention target tissue may be tissuelocated in a region having an average of 100 sweat glands per squarecentimeter. In embodiments of the invention target tissue may be tissuelocated approximately 0.5 millimeters to 6 millimeters below the surfaceof the skin. In embodiments of the invention target tissue may be tissuelocated in a region where sweat glands, including, for example, apocrineand eccrine glands are located. In embodiments of the invention targettissue may be tissue located in a region where hair follicles arelocated.

Tissue Properties

In embodiments of the invention target tissue may be tissue subject todielectric heating. In embodiments of the invention target tissue may betissue having a high dipole moment. In embodiments of the invention,target tissue may be, for example, tissue containing exogenousmaterials. In embodiments of the invention target tissue may includetissue with bacteria. In embodiments of the invention target tissue maybe, for example, collagen, hair follicles, cellulite, eccrine glands,apocrine glands, sebaceous glands or spider veins. In embodiments of theinvention target tissue may be, for example, hair follicles. Inembodiments of the invention target tissue may be, for example, regionsof a hair follicle, including the lower segment (bulb and suprabulb),the middle segment (isthmus), and the upper segment (infundibulum). Inembodiments of the invention target tissue may be, for example,structures associated with a hair follicle, such as, for example, stemcells.

Tissue Types

In embodiments of the invention target tissue may be human tissue. Inembodiments of the invention target tissue may be porcine tissue. Inembodiments of the invention target tissue may be, for example, woundtissue. In embodiments of the invention target tissue may be, forexample, tissue to be insulted, as for example, skin tissue prior tosurgery. In embodiments of the invention target tissue may be, forexample, vessels, including veins, capillaries or arteries, supplyingblood to tissue structures.

Effect

In embodiments of the invention, target tissue may be, for example, avolume of tissue defined by a region with a SAR greater than or equal toapproximately fifty percent of peak SAR. In embodiments of theinvention, target tissue may be, for example, a volume of tissue definedby a region with a SAR greater than or equal to between thirty andseventy percent of peak SAR.

Methods Tissue & Structures

In one embodiment of the invention a method of treating target tissue isdescribed. In one embodiment of the invention a method of damagingglands is described. In one embodiment of the invention a method ofdamaging hair follicles is described. In one embodiment of the inventiona method of destroying tissue is described. In one embodiment of theinvention a method of treating skin tissue is described. In oneembodiment of the invention a method of preventing damage to tissue isdescribed. In one embodiment of the invention a method of preventing thegrowth of a lesion toward a skin surface is described. In one embodimentof the invention, a method of damaging or destroying stem cellsassociated with hair follicles is described. In one embodiment of theinvention, a method of aligning electromagnetic fields to preferentiallytreat tissue is described. In one embodiment of the invention, a methodof aligning electromagnetic fields to preferentially treat tissue havinga high water content is described. In embodiments of the invention,electromagnetic energy is used to heat sebum. In one embodiment of theinvention, a method of creating a lesion in selected tissue regions isdescribed. In one embodiment of the invention, a method of selectivelydepositing energy in selected tissue regions is described. In oneembodiment of the invention, a method of selectively heating regions oftissue is described. In one embodiment of the invention, a method ofpreferentially heating regions of tissue is described.

Radiation

In one embodiment of the invention, a method of controlling powerdeposition in tissue is described. In one embodiment of the invention, amethod of controlling E-field pattern in tissue is described. In oneembodiment of the invention a method of creating a volume of high powerdeposition in tissue is described. In one embodiment of the invention amethod of controlling output of a microwave device is described.

Lesion

In one embodiment of the invention a method of creating a lesion intissue is described. In one embodiment of the invention a method ofcreating a subdermal lesion in tissue is described.

Gradients

In one embodiment of the invention a method of creating a temperaturegradient within tissue is described. In one embodiment of the inventiona method of creating a temperature gradient having a peak at a dermal,hypodermal interface is described. In one embodiment of the invention amethod of creating a temperature gradient having a peak in dermal tissueadjacent the dermal, hypodermal interface is described. In oneembodiment of the invention a method of creating a temperature gradienthaving a peak in glandular tissue is described. In one embodiment of theinvention a method of creating a temperature gradient having a peak inglandular tissue adjacent an interface between glandular tissue andhypodermal tissue is described. In one embodiment of the invention amethod of creating a temperature gradient having a peak adjacent acritical interface is described. In one embodiment of the invention amethod of creating an inverse power gradient in tissue is described.

Clinical Indications

In one embodiment of the invention a method of reducing sweat isdescribed. In one embodiment of the invention a method of reducing sweatproduction in a patient is described. In one embodiment of the inventiona method of treating axillary hyperhidrosis is described. In oneembodiment of the invention a method of treating hyperhidrosis isdescribed. In one embodiment of the invention a method of removing hairis described. In one embodiment of the invention a method of preventingthe re-growth of hair is described. In one embodiment of the invention,a method of treating osmidrosis is described. In one embodiment of theinvention, a method of denervating tissue is described. In oneembodiment of the invention, a method of treating port wine stains isdescribed. In one embodiment of the invention, a method of treatinghemangiomas is described. In one embodiment of the invention, a methodof treating psoriasis is described. In one embodiment of the invention,a method of reducing sweat is described. In one embodiment of theinvention, a method of reducing sweat is described. In embodiments ofthe invention, electromagnetic energy is used to treat acne. In oneembodiment of the invention, a method of treating sebaceous glands isdescribed. In one embodiment of the invention, a method of destroyingbacteria is described. In one embodiment of the invention, a method ofdestroying propionibacterium is described. In one embodiment of theinvention, a method of treating reducing inflammation is described.Further conditions and structures that can be treated in someembodiments are described in, for example, pp. 3-7 of U.S. ProvisionalApp. No. 60/912,899; and pp. 1-10 of U.S. Provisional App. No.61/013,274 both incorporated by reference in their entireties, as wellas illustrated and described in, for example, pp. 8-12 of Appendix 1 andpp. 5-14 of Appendix 2.

In one embodiment of the invention electromagnetic energy may be used toreduce sweat. In one embodiment of the invention electromagnetic energymay be used to reduce sweat production in a patient. In one embodimentof the invention electromagnetic energy may be used to treat axillaryhyperhidrosis. In one embodiment of the invention electromagnetic energymay be used to treat hyperhidrosis. In one embodiment of the inventionelectromagnetic energy may be used to remove hair. In one embodiment ofthe invention electromagnetic energy may be used to prevent there-growth of hair. In one embodiment of the invention electromagneticenergy may be used to treat osmidrosis. In one embodiment of theinvention, electromagnetic energy may be used to denervate tissue. Inone embodiment of the invention electromagnetic energy may be used totreat port wine stains. In one embodiment of the inventionelectromagnetic energy may be used to treat hemangiomas. In oneembodiment of the invention electromagnetic energy may be used to treatpsoriasis. In one embodiment of the invention electromagnetic energy maybe used to reduce sweat. In embodiments of the invention,electromagnetic energy may be used to treat acne. In embodiments of theinvention, electromagnetic energy may be used to treat sebaceous glands.In embodiments of the invention, electromagnetic energy may be used todestroy bacteria. In embodiments of the invention, electromagneticenergy may be used to destroy propionibacterium. In embodiments of theinvention, electromagnetic energy may be used to clear sebum from a hairfollicle. In embodiments of the invention, electromagnetic energy may beused to clear obstructed hair follicles. In embodiments of theinvention, electromagnetic energy may be used to reverse comedogenesis.In embodiments of the invention, electromagnetic energy may be used toclear blackheads. In embodiments of the invention, electromagneticenergy may be used to clear whiteheads. In embodiments of the invention,electromagnetic energy may be used to reducing inflammation.

Positioning

In one embodiment of the invention a method of positioning skin isdescribed. In one embodiment of the invention a method of positioning adermal, hypodermal interface is described. In one embodiment of theinvention a method of positioning a critical interface is described. Inone embodiment of the invention a method of positioning a skin, fatinterface is described. In one embodiment of the invention a method ofpositioning an interface between a glandular layer and a layer ofhypodermal tissue is described. In one embodiment of the invention amethod of separating target tissue from muscle is described. In oneembodiment of the invention a method of separating skin tissue frommuscle is described.

Power Loss Density or Specific Absorption Rate Skin

In one embodiment of the invention, irradiating tissue through thesurface of skin with electromagnetic radiation results in a region oflocalized high power loss density or SAR below the skin surface. In oneembodiment of the invention, irradiating tissue through the surface ofskin with electromagnetic radiation results in a region of localizedhigh power loss density or SAR in a region of the skin below an upperlayer of the skin. In one embodiment of the invention, irradiatingtissue through the surface of skin with electromagnetic radiationgenerates a region of localized high power loss density or SAR in alayer of the skin adjacent a critical interface. In one embodiment ofthe invention, irradiating tissue through the surface of skin withelectromagnetic radiation generates a region of localized high powerloss density or SAR in a layer of the skin adjacent a critical interfaceand between the skin surface and the critical interface.

Dermis

In one embodiment of the invention, irradiating tissue through thesurface of skin with electromagnetic radiation generates a region oflocalized high power loss density or SAR in a region of the dermis. Inone embodiment of the invention, radiating the surface of skin withelectromagnetic radiation generates a region of localized high powerloss density or SAR in a region of the dermis below an upper layer ofthe dermis. In one embodiment of the invention, irradiating tissuethrough the surface of skin with electromagnetic radiation generates aregion of localized high power loss density or SAR in a region of thedermis adjacent an interface between the dermis and the epidermis. Inone embodiment of the invention, irradiating tissue through the surfaceof skin with electromagnetic radiation generates a region of localizedhigh power loss density or SAR in a region of the dermis adjacent acritical interface.

In embodiments of the invention, regions of localized high power lossdensity or regions of localized high specific absorption rate result inthe deposition of sufficient energy into those regions to raise thetemperature of those regions above the temperature of surroundingregions. In embodiments of the invention, regions of localized highpower loss density or regions of localized high specific absorption rateresult in the deposition of sufficient energy into those regions toraise the temperature of those regions to a temperature sufficient tocreate lesions in those regions. In embodiments of the invention,regions of localized high power loss density or regions of localizedhigh specific absorption rate result in the deposition of sufficientenergy into those regions to raise the temperature of those regions to atemperature sufficient to heat surrounding regions by, for example,thermal conductive heating.

Glandular Layer

In one embodiment of the invention, irradiating tissue through thesurface of skin with electromagnetic radiation generates a region oflocalized high power loss density or SAR in a glandular layer. In oneembodiment of the invention, irradiating tissue through the surface ofskin with electromagnetic radiation generates a region of localized highpower loss density or SAR in a glandular layer adjacent a criticalinterface. In one embodiment of the invention, irradiating tissuethrough the surface of skin with electromagnetic radiation generates aregion of localized high power loss density or SAR in a glandular layeradjacent a critical interface and below a first layer of skin. In oneembodiment of the invention, irradiating tissue through the surface ofskin with electromagnetic radiation generates a region of localized highpower loss density or SAR in a glandular layer adjacent a criticalinterface and below at least a portion of the dermis.

Temperature Gradient Skin

In one embodiment of the invention, irradiating tissue through thesurface of skin with electromagnetic radiation generates a temperaturegradient having a peak in a region below the skin surface. In oneembodiment of the invention, irradiating tissue through the surface ofskin with electromagnetic radiation generates a temperature gradienthaving a peak in a region of the skin below an upper layer of the skin.In one embodiment of the invention, irradiating tissue through thesurface of skin with electromagnetic radiation generates a temperaturegradient having a peak in a layer of the skin adjacent to a criticalinterface. In one embodiment of the invention, irradiating tissuethrough the surface of skin with electromagnetic radiation generates atemperature gradient having a peak in a layer of the skin adjacent to acritical interface and between a critical interface and the surface ofthe skin.

Dermis

In one embodiment of the invention, electromagnetic radiation generatesa temperature gradient where the temperature gradient has a peak in alayer of the dermis below the surface of the skin. In one embodiment ofthe invention, electromagnetic radiation generates a temperaturegradient where the temperature gradient has a peak in a layer of thedermis below an upper layer of the dermis. In one embodiment of theinvention, electromagnetic radiation generates a temperature gradientwhere the temperature gradient has a peak in a region of the dermisadjacent an interface between the dermis and the hypodermis. In oneembodiment of the invention, electromagnetic radiation generates atemperature gradient where the temperature gradient has a peak in aregion of the dermis adjacent a critical interface.

Glandular Layer

In one embodiment of the invention irradiating tissue through thesurface of skin with electromagnetic radiation generates a temperaturegradient having a peak in a glandular layer below the skin surface. Inone embodiment of the invention, irradiating tissue through the surfaceof skin with electromagnetic radiation generates a temperature gradienthaving a peak in a glandular layer adjacent a critical interface. In oneembodiment of the invention, irradiating tissue through the surface ofskin with electromagnetic radiation generates a temperature gradienthaving a peak in a glandular layer adjacent a critical interface andbelow a first layer of skin.

Inverse Power Gradient Skin

In one embodiment of the invention, irradiating tissue through thesurface of skin with electromagnetic radiation generates an inversepower gradient having a peak in a region below the skin surface. In oneembodiment of the invention, irradiating tissue through the surface ofskin with electromagnetic radiation generates an inverse power gradienthaving a peak in a region of the skin below an upper layer of the skin.In one embodiment of the invention, irradiating tissue through thesurface of skin with electromagnetic radiation generates an inversepower gradient having a peak in a layer of the skin adjacent to acritical interface. In one embodiment of the invention, irradiatingtissue through the surface of skin with electromagnetic radiationgenerates an inverse power gradient having a peak in a layer of the skinadjacent to a critical interface and between a critical interface andthe surface of the skin.

Dermis

In one embodiment of the invention, electromagnetic radiation generatesan inverse power gradient where the inverse power gradient has a peak ina layer of the dermis below the surface of the skin. In one embodimentof the invention, electromagnetic radiation generates an inverse powergradient where the inverse power gradient has a peak in a layer of thedermis below an upper layer of the dermis. In one embodiment of theinvention, electromagnetic radiation generates an inverse power gradientwhere the inverse power gradient has a peak in a region of the dermisadjacent an interface between the dermis and the hypodermis. In oneembodiment of the invention, electromagnetic radiation generates aninverse power gradient where the inverse power gradient has a peak in aregion of the dermis adjacent a critical interface.

Glandular Layer

In one embodiment of the invention irradiating tissue through thesurface of skin with electromagnetic radiation generates an inversepower gradient having a peak in a glandular layer below the skinsurface. In one embodiment of the invention, irradiating tissue throughthe surface of skin with electromagnetic radiation generates an inversepower gradient having a peak in a glandular layer adjacent a criticalinterface. In one embodiment of the invention, irradiating tissuethrough the surface of skin with electromagnetic radiation generates aninverse power gradient having a peak in a glandular layer adjacent acritical interface and below a first layer of skin.

Lesion Skin

In one embodiment of the invention, electromagnetic radiation is used tocreate a lesion in a region below the skin surface. In one embodiment ofthe invention, electromagnetic radiation is used to create a lesion in aregion below the skin surface where the lesion starts in a layer belowan upper layer of the skin. In one embodiment of the invention, is usedto create a lesion in skin where the lesion starts in a layer of theskin adjacent a critical interface. In one embodiment of the invention,is used to create a lesion in skin where the lesion starts in a layer ofthe skin adjacent a critical interface and between the skin surface andthe critical interface.

Dermis

In one embodiment of the invention, electromagnetic radiation is used tocreate a lesion in skin where the lesion starts in a layer of the dermisbelow the surface of the skin. In one embodiment of the invention,electromagnetic radiation is used to create a lesion in skin where thelesion starts in a layer of the dermis below an upper layer of thedermis. In one embodiment of the invention, electromagnetic radiation isused to create a lesion in skin, where the lesion starts in a region ofthe dermis in close proximity to the interface between the dermis andthe hypodermis. In one embodiment of the invention, electromagneticradiation is used to create a lesion in skin, where the lesion starts ina region of the dermis adjacent a critical interface.

Glandular Layer

In one embodiment of the invention, electromagnetic radiation is used tocreate a lesion which starts in a glandular layer. In one embodiment ofthe invention, electromagnetic radiation is used to create a lesionwhich starts in a glandular layer adjacent a critical interface. In oneembodiment of the invention, electromagnetic radiation is used to createa lesion which starts in a glandular layer adjacent a critical interfaceand below a first layer of skin.

Skin

In one embodiment of the invention, electromagnetic radiation is used tocreate a lesion in a region below the skin surface in the absence of anyexternal mechanism for removing heat from the surface of the skin. Inone embodiment of the invention, electromagnetic radiation is used tocreate a lesion in a region below the skin surface where the lesionstarts in a layer below an upper layer of the skin in the absence of anyexternal mechanism for removing heat from the surface of the skin. Inone embodiment of the invention, is used to create a lesion in skinwhere the lesion starts in a layer of the skin adjacent a criticalinterface in the absence of any external mechanism for removing heatfrom the surface of the skin. In one embodiment of the invention, isused to create a lesion in skin where the lesion starts in a layer ofthe skin adjacent a critical interface and between the skin surface andthe critical interface in the absence of any external mechanism forremoving heat from the surface of the skin.

Dermis

In one embodiment of the invention, electromagnetic radiation is used tocreate a lesion in skin where the lesion starts in a layer of the dermisbelow the surface of the skin in the absence of any external mechanismfor removing heat from the surface of the skin. In one embodiment of theinvention, electromagnetic radiation is used to create a lesion in skinwhere the lesion starts in a layer of the dermis below an upper layer ofthe dermis in the absence of any external mechanism for removing heatfrom the surface of the skin. In one embodiment of the invention,electromagnetic radiation is used to create a lesion in skin, where thelesion starts in a region of the dermis in close proximity to theinterface between the dermis and the hypodermis in the absence of anyexternal mechanism for removing heat from the surface of the skin. Inone embodiment of the invention, electromagnetic radiation is used tocreate a lesion in skin, where the lesion starts in a region of thedermis adjacent a critical interface in the absence of any externalmechanism for removing heat from the surface of the skin.

Glandular Layer

In one embodiment of the invention, electromagnetic radiation is used tocreate a lesion which starts in a glandular layer in the absence of anyexternal mechanism for removing heat from the surface of the skin. Inone embodiment of the invention, electromagnetic radiation is used tocreate a lesion which starts in a glandular layer adjacent a criticalinterface in the absence of any external mechanism for removing heatfrom the surface of the skin. In one embodiment of the invention,electromagnetic radiation is used to create a lesion which starts in aglandular layer adjacent a critical interface and below a first layer ofskin in the absence of any external mechanism for removing heat from thesurface of the skin.

Lesion Origin

In one embodiment of the invention, a lesion origin may be located at apoint or region in high dielectric, high conductivity tissue adjacentlow dielectric tissue. In one embodiment of the invention, a lesionorigin may be a point or region in tissue where a tissue reaches atemperature sufficient to allow a lesion to begin to grow. In oneembodiment of the invention, a lesion origin may be located at a pointor region in high dielectric, high conductivity tissue adjacent acritical interface. In one embodiment of the invention, the lesionorigin may be located at a point or region where microwave energyradiated through the surface of the skin generates a standing wavepattern having a peak E-field. In one embodiment of the invention, thelesion origin may be located in high dielectric/high conductivity tissuenear a critical interface where microwave energy radiated through thesurface of the skin generates constructive interference.

Electromagnetic Radiation Characteristics

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific E-field characteristics. In one embodiment of theinvention, skin is irradiated with electromagnetic radiation wherein thepolarization of the E-field component of the electromagnetic radiationis substantially parallel to the skin's outer surface. In one embodimentof the invention, skin is irradiated with electromagnetic radiationwherein the E-field component of the electromagnetic radiation issubstantially parallel to at least one interface between tissue layerswithin the skin. In one embodiment of the invention, skin is irradiatedwith electromagnetic radiation wherein the E-field component of theelectromagnetic radiation is substantially parallel to a criticalinterface. In one embodiment of the invention, skin is irradiated withelectromagnetic radiation wherein the E-field component of theelectromagnetic radiation is substantially parallel to the interfacebetween the dermis and the hypodermis. In one embodiment of theinvention, skin is irradiated with electromagnetic radiation wherein theE-field component of the electromagnetic radiation is substantiallyparallel to the interface between a glandular layer and a portion of thehypodermis. In one embodiment of the invention, an E-field component maybe considered to be substantially parallel to, for example, a criticalinterface when such E-field component is substantially parallel to anidealized average interface, such as, for example, the idealizedinterface 1308 or 1333 used in the Figures. In one embodiment of theinvention, an E-field component may be considered to be substantiallyparallel to, for example, a critical interface when such E-fieldcomponent is substantially parallel to at least a portion of suchinterface, such as, for example, a portion of such interface underlyingan aperture of an antenna radiating the E-field.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific polarization characteristics. In one embodimentof the invention, skin is irradiated with electromagnetic radiationwherein the electromagnetic radiation is polarized such that the E-fieldcomponent of the electromagnetic radiation is substantially parallel tothe skin's outer surface. In one embodiment of the invention, skin isirradiated with electromagnetic radiation wherein the electromagneticradiation is polarized such that the E-field component of theelectromagnetic radiation is substantially parallel to at least oneinterface between tissue layers within the skin. In one embodiment ofthe invention, skin is irradiated with electromagnetic radiation whereinthe electromagnetic radiation is polarized such that the E-fieldcomponent of the electromagnetic radiation is substantially parallel tothe interface between the dermis and the hypodermis. In one embodimentof the invention, skin is irradiated with electromagnetic radiationwherein the electromagnetic radiation is polarized such that the E-fieldcomponent of the electromagnetic radiation is substantially parallel toan interface between a glandular layer and the hypodermis.

In one embodiment of the invention, an E-field may be made up of atleast two E-field components, wherein one of said E-field components isparallel to a skin surface or a critical interface and a second E-fieldcomponent is perpendicular to the first E-field component. In oneembodiment of the invention, an E-field may be substantially parallel toa surface or interface when the magnitude of an E-field componentparallel to that surface or interface is greater than 75 percent of thetotal E-field magnitude. In one embodiment of the invention, an E-fieldmay be made up of a transverse E-field component and a perpendicularE-field component. In one embodiment of the invention, an E-field may bemade up a transverse E-field component may be parallel to a skin surfaceor a critical interface. In one embodiment of the invention, an E-fieldmay be substantially parallel to a surface or interface when themagnitude of a transverse E-field component is greater than 75 percentof the total E-field magnitude.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific frequency characteristics. In one embodiment ofthe invention, skin is irradiated by electromagnetic radiation having afrequency of approximately 5.8 GHz. In one embodiment of the invention,skin is irradiated by electromagnetic radiation having a frequency ofbetween 5 GHz and 6.5 GHz. In one embodiment of the invention, skin isirradiated by electromagnetic radiation having a frequency of between4.0 GHz and 10 GHz.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics within tissue. In one embodimentof the invention, skin is irradiated by electromagnetic radiation whichgenerates a constructive interference pattern having a peak within theskin. In one embodiment of the invention, skin is irradiated byelectromagnetic radiation which generates a constructive interferencepattern in the dermis, wherein the constructive interference pattern hasa peak in a region of the dermis which is below a first layer of thedermis and where destructive interference occurs in the first layer ofthe dermis. In one embodiment of the invention, skin is irradiated byelectromagnetic radiation which generates a constructive interferencepattern, wherein the constructive interference pattern has a peakadjacent a critical interface. In one embodiment of the invention, skinis irradiated by electromagnetic radiation which generates aconstructive interference pattern having a peak in a glandular layer. Inone embodiment of the invention, skin irradiated with electromagneticradiation generates a constructive interference pattern that generates apeak electric field in a tissue layer. In one embodiment of theinvention, skin irradiated with electromagnetic radiation generates aconstructive interference pattern that generates a region of localizedhigh power loss density, SAR or tissue temperature.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics within skin. In one embodiment ofthe invention, skin is irradiated by electromagnetic radiation whichgenerates a destructive interference pattern within the skin. In oneembodiment of the invention, skin irradiated with electromagneticradiation generates a destructive interference pattern that generates aminimum electric field in a tissue layer. In one embodiment of theinvention, skin irradiated with electromagnetic radiation generates adestructive interference pattern that generates a region of localizedlow power loss density, SAR or tissue temperature. In one embodiment ofthe invention, skin is irradiated by electromagnetic radiation whichgenerates a destructive interference pattern in the dermis, wherein thedestructive interference pattern has a peak in a region of the dermiswhich is above a deep layer of the dermis. In one embodiment of theinvention, skin is irradiated by electromagnetic radiation whichgenerates a destructive interference pattern having a peak in tissuebetween a skin surface and a glandular layer.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics within tissue. In one embodimentof the invention, skin is irradiated by electromagnetic radiation whichgenerates a standing wave pattern within the skin. In one embodiment ofthe invention, skin is irradiated by electromagnetic radiation whichgenerates a standing wave pattern having a peak in the dermis below afirst layer of the dermis. In one embodiment of the invention, skin isirradiated by electromagnetic radiation which generates a standing wavepattern having a peak adjacent a critical interface. In one embodimentof the invention, skin is irradiated by electromagnetic radiation whichgenerates a standing wave pattern having a peak in a glandular layer. Inone embodiment of the invention, skin irradiated with electromagneticradiation generates a standing wave pattern that generates a peakelectric field. In one embodiment of the invention, skin irradiated withelectromagnetic radiation generates a standing wave pattern thatgenerates a region of localized high power loss density, SAR or tissuetemperature. In one embodiment of the invention, skin irradiated withelectromagnetic radiation generates a standing wave pattern thatgenerates a region of localized low power loss density, SAR or tissuetemperature.

Antenna

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics resulting from the position ofthe antenna radiating the electromagnetic radiation. In one embodimentof the invention, skin is irradiated by electromagnetic radiationgenerated by an antenna positioned in close proximity to the skinsurface. In one embodiment of the invention, skin is irradiated by anantenna located in the radiating near field region with respect to thesurface of adjacent skin. In one embodiment of the invention, skin isirradiated by an antenna located substantially in the radiating nearfield region with respect to the surface of adjacent skin. In oneembodiment of the invention, skin is irradiated by an antenna locatedless than one half of one wavelength from the surface of adjacent skin.In one embodiment of the invention, skin is irradiated by an antennalocated less than one half of one wavelength from the surface ofadjacent skin, wherein a wavelength is measured in dielectric materialseparating the antenna from the skin surface. In one embodiment of theinvention, skin is irradiated by an antenna located less than one halfof one wavelength from the surface of adjacent skin, wherein awavelength is measured in cooling fluid separating the antenna from theskin surface. In one embodiment of the invention, skin is irradiated byan antenna located less approximately 3 millimeters from the skinsurface. In one embodiment of the invention, skin is irradiated by anantenna located less approximately 1.5 millimeters from the skinsurface. In one embodiment of the invention, wavelength of a radiatedsignal is the wavelength in air divided by the square root of thedielectric constant of materials separating the antenna from the skinsurface. In one embodiment of the invention, wavelength of a radiatedsignal is the wavelength in air divided by the square root of thedielectric constant of cooling fluid separating the antenna from theskin surface.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics resulting from the position ofthe output of the antenna radiating the electromagnetic radiation. Inone embodiment of the invention, skin is irradiated by an antenna havingan output in the radiating near field region with respect to the surfaceof adjacent skin. In one embodiment of the invention, skin is irradiatedby an antenna having an output outside the reactive near field regionwith respect to the surface of adjacent skin. In one embodiment of theinvention, skin is irradiated by an antenna having an output which isnot in the far field region with respect to the surface of adjacentskin.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics related to the position of aradiating aperture in the antenna radiating the electromagneticradiation. In one embodiment of the invention, skin is irradiated by anantenna having a radiating aperture in the radiating near field regionwith respect to the surface of adjacent skin. In one embodiment of theinvention, skin is irradiated by an antenna having a radiating apertureoutside the reactive near field with respect to the surface of adjacentskin. In one embodiment of the invention, skin is irradiated by anantenna having a radiating aperture which is not in the far field regionwith respect to the surface of adjacent skin.

In one embodiment of the invention, a reactive near field region may be,for example, that portion of the near field region immediatelysurrounding the antenna where the near reactive field predominates. Inone embodiment of the invention, an antenna may be located a distancefrom a skin surface which may be approximately 0.62 times the squareroot of D³/Lambda, where D is the largest physical dimension of theantenna aperture and Lambda is the wavelength of the electromagneticradiation transmitted by the antenna measured in the medium positionedbetween the antenna output and skin surface. In one embodiment of theinvention, a radiating near field region may be, for example, that thatregion of the field of an antenna between the reactive near field regionand the far field region wherein radiation fields predominate. In oneembodiment of the invention, an antenna may be located a maximumdistance from a skin surface which may be approximately 2 timesD²/Lambda, where D is the largest physical dimension of the antennaaperture and Lambda is the wavelength of the electromagnetic radiationtransmitted by the antenna measured in the medium positioned between theantenna output and skin surface. In one embodiment of the invention, anantenna may be located a less than approximately 2 times D²/Lambda Inone embodiment of the invention, a far field region may be, for example,that region of the field of an antenna where the angular fielddistribution is essentially independent of the distance from theantenna.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics resulting from the configurationof the antenna which radiates the electromagnetic radiation. In oneembodiment of the invention, skin is irradiated by an antenna configuredto radiate a field pattern primarily in the TE mode. In one embodimentof the invention, skin is irradiated by an antenna configured to radiatea field pattern primarily in the TE₁₀ mode. In one embodiment of theinvention, skin is irradiated by an antenna configured to radiate afield pattern solely in TE₁₀ mode. In one embodiment of the invention,skin is irradiated by an antenna configured to radiate a field patternprimarily in the TEM mode. In one embodiment of the invention, skin isirradiated by an antenna configured to radiate a field pattern solely inTEM mode. In embodiments of the invention, TE, TEM and TE₁₀ areparticularly useful as they are modes in which radiated electromagneticenergy includes E-Fields in the transverse direction. Thus, where anantenna is positioned appropriately, an antenna transmittingelectromagnetic energy in a TE, TEM or TE₁₀ mode will generate anE-field which may be parallel or substantially parallel to a skinsurface adjacent the antenna or to a critical interface, such as, forexample, an interface between the dermis and the hypodermis.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics resulting from the configurationof the antenna which radiates the electromagnetic radiation. In oneembodiment of the invention, skin is irradiated by an antenna configuredto radiate electromagnetic energy having an E-field component which issubstantially parallel to the surface of the skin. In one embodiment ofthe invention, skin is irradiated by an antenna configured to radiateelectromagnetic energy having an E-field component which issubstantially parallel to a critical interface. In one embodiment of theinvention, skin is irradiated by an antenna configured to radiateelectromagnetic energy having an E-field component which issubstantially parallel to the interface between the dermis and thehypodermis. In one embodiment of the invention, skin is irradiated by anantenna configured to radiate electromagnetic energy having an E-fieldcomponent which is substantially parallel to an interface between aglandular region and a portion of the hypodermis.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics resulting from the configurationof the antenna which radiates the electromagnetic radiation. In oneembodiment of the invention, skin is irradiated by an antenna configuredto generate a standing wave in adjacent tissue. In one embodiment of theinvention, skin is irradiated by an antenna configured to generate astanding wave in adjacent tissue wherein the standing wave has a peakadjacent a critical interface. In one embodiment of the invention, skinis irradiated by an antenna configured to generate a standing wave inadjacent tissue wherein the standing wave has a peak in dermal tissueadjacent a dermal, subdermal interface. In one embodiment of theinvention, skin is irradiated by an antenna configured to generate astanding wave in adjacent tissue wherein the standing wave has a peak ina glandular layer.

In one embodiment of the invention, skin is irradiated byelectromagnetic radiation having specific characteristics and, moreparticularly, specific characteristics resulting from the configurationof the antenna which radiates the electromagnetic radiation. In oneembodiment of the invention, skin is irradiated by an antenna configuredto generate constructive interference in adjacent tissue. In oneembodiment of the invention, skin is irradiated by an antenna configuredto generate constructive interference in adjacent tissue wherein theconstructive interference has a peak adjacent a critical interface. Inone embodiment of the invention, skin is irradiated by an antennaconfigured to generate constructive interference in adjacent tissuewherein the standing wave has a peak in dermal tissue adjacent a dermal,subdermal interface. In one embodiment of the invention, skin isirradiated by an antenna configured to generate constructiveinterference in adjacent tissue wherein the standing wave has a peak ina glandular layer.

Heating Tissue/Tissue Structures

In one embodiment of the invention, tissue is heated by conducting heatgenerated in a lesion to specified tissue. In one embodiment of theinvention, tissue is heated by conducting heat generated in a lesionthrough intermediate tissue wherein heat in the lesion is generatedprimarily by dielectric heating. In one embodiment of the invention,tissue located below a critical interface is heated by conducting heatgenerated in a lesion across the critical interface. In one embodimentof the invention, a method is described for heating tissue located belowa critical interface by conducting heat generated in a lesion locatedabove the critical interface wherein heat generated in the lesion isgenerated primarily by dielectric heating and heat below the criticalinterface is generated primarily by conduction of heat from the lesionthrough intermediate tissue to tissue located below a dielectricbarrier.

In one embodiment of the invention, tissue structures, such as, forexample sweat glands or hair follicles, located in the region of theskin near a critical interface are heated. In one embodiment of theinvention, tissue structures located near a critical interface areheated primarily by conduction of heat from a lesion. In one embodimentof the invention, tissue structures located near a critical interfaceare heated primarily by conduction of heat from a lesion, wherein thelesion is created by dielectric heating. In one embodiment of theinvention, tissue structures located in a first tissue layer are heatedby heat generated in the first tissue layer as a result of a standingwave generated in the first tissue layer by reflections off a criticalinterface

In one embodiment of the invention, tissue structures located in theregion of the skin where the dermis and hypodermis layer meet areheated. In one embodiment of the invention, tissue structures located ina glandular layer are heated. In one embodiment of the invention, tissuestructures located in the region of the skin where the dermis andhypodermis layer meet are damaged. In one embodiment of the invention,tissue structures located in a glandular layer are damaged. In oneembodiment of the invention, tissue structures located in the region ofthe skin where the dermis and hypodermis layer meet are destroyed. Inone embodiment of the invention, tissue structures located in aglandular layer are destroyed. In one embodiment of the invention,tissue elements are heated by conducting heat generated in a lesionthrough intermediate tissue to the tissue elements, wherein heat in thelesion is generated primarily by dielectric heating. In one embodimentof the invention, tissue structures located below a critical interfaceare heated by conducting heat generated in a lesion above the criticalinterface primarily by dielectric heating through intermediate tissue totissue structures located below a the critical interface.

In one embodiment of the invention a region adjacent a criticalinterface may be heated by depositing more energy into that region thaninto surrounding tissue. In one embodiment of the invention, tissue inthe dermal layer, adjacent to the interface between the dermal layer andthe subdermal layer is preferentially heated. In one embodiment of theinvention, tissue in a glandular layer is preferentially heated. In oneembodiment of the invention, tissue in a glandular layer adjacent acritical interface is preferentially heated.

Cooling

In one embodiment of the invention, heat generated in tissue below thesurface of the skin is prevented from damaging tissue adjacent thesurface of the skin by removing heat from the surface of the skin. Inone embodiment of the invention, heat generated in tissue below thesurface of the skin is prevented from damaging tissue adjacent thesurface of the skin by cooling the surface of the skin.

In one embodiment of the invention, a method is described for preventingheat generated in a lesion by dielectric heating from damaging tissue ina skin layer positioned between the lesion and the surface of the skin.In one embodiment of the invention, a method is described for preventingheat generated in a lesion by dielectric heating from damaging tissue ina skin layer positioned between the lesion and the surface of the skinby removing heat from a skin surface. In one embodiment of theinvention, a method is described for preventing heat generated in alesion by dielectric heating from damaging tissue in a skin layerpositioned between the lesion and the surface of the skin by cooling askin surface.

In one embodiment of the invention, a method is described for preventingheat generated in a lesion having an origin in a layer of tissue fromdamaging tissue in a layer of tissue positioned between the lesionorigin and the surface of the skin. In one embodiment of the invention,a method is described for preventing heat generated in a lesion havingan origin in a layer of tissue from damaging tissue in a skin layerpositioned between the lesion and the surface of the skin by removingheat from a skin surface. In one embodiment of the invention, a methodis described for preventing heat generated in a lesion having an originin a layer of tissue from damaging tissue in a skin layer positionedbetween the lesion and the surface of the skin by cooling a skinsurface.

In one embodiment of the invention, a method is described for preventinglesion from growing toward the surface of the skin. In one embodiment ofthe invention, a method is described for preventing lesion from growingtoward the surface of the skin by removing heat from the skin surface.In one embodiment of the invention, a method is described for preventinglesion from growing toward the surface of the skin by cooling the skinsurface.

In one embodiment of the invention, cooling may be turned off for aperiod after energy is delivered and resumed thereafter. In oneembodiment of the invention, cooling may be turned off for a period offor example, approximately 2 seconds after energy is delivered. In oneembodiment of the invention, cooling turned on and off in a pulsedmanner to control the amount of heat removed through the skin surface.

Antenna System Antenna Types

In embodiments of the invention, antenna 358 may be, for example: acoaxial single slot antenna; a coaxial multiple slot antenna; a printedslot antenna; a waveguide antenna; a horn antenna; a patch antenna; apatch trace antenna; a Vivaldi antenna; or a waveguide antenna. Inembodiments of the invention, an antenna may be, for example an array ofantennas. In embodiments of the invention, an antenna may be, forexample an array of antennas wherein one or more of the antennas radiateelectromagnetic energy at the same time. In embodiments of theinvention, an antenna may be, for example an array of antennas whereinat least one but not all of the antennas radiate electromagnetic energyat the same time. In embodiments of the invention, an antenna may be,for example, two or more different types of antennas. In embodiments ofthe invention, specific antennas in an array may be selectivelyactivated or deactivated. Additional embodiments of antennas that can beused in conjunction with embodiments and components of the presentapplication can be found, for example, in U.S. Provisional ApplicationNo. 60/912,899, entitled METHODS AND APPARATUS FOR REDUCING SWEATPRODUCTION, filed Apr. 19, 2007, incorporated by reference in itsentirety, e.g., in FIGS. 3, 4, 5, 6C, 12F, 34A, and 38 and theaccompanying description, as well as in U.S. Provisional Application No.61/013,274, entitled METHODS, DEVICES, AND SYSTEMS FOR NON-INVASIVEDELIVERY OF MICROWAVE THERAPY, filed Dec. 12, 2007 and incorporated byreference in its entirety, e.g., in FIGS. 2C, 3A, 5, 6, 11A, 11B, 20,21A, 21B, 22, 22A and 23.

Return Loss/Bandwidth

In one embodiment of the invention, an antenna has an optimized returnloss (S₁₁) profile centered on 5.8 GHz. S11 in dB or return loss (themagnitude of S₁₁ in dB) is a measure of reflected power measured atantenna feed divided by the incident power at the antenna feed, which itmay be used as a power transfer measurement. In one embodiment of theinvention, an antenna has an optimal coupling value may be, for example,−15 dB or below, which corresponds to 97% power return loss. At 97%power coupling, 97% of the input power available to the antenna (e.g.,from a microwave generator) is coupled into the antenna's input port.Alternatively, in one embodiment of the invention, an antenna has anoptimal coupling value of, for example, −10 dB or below, whichcorresponds to 90% power coupling. Alternatively, in one embodiment ofthe invention, an antenna has an optimal coupling value which may be,for example, −7 dB or below, which corresponds to 80% power coupling. Inone embodiment of the invention, an antenna, such as, for example, awave guide antenna may include tuning screws. In one embodiment of theinvention, tuning screws may be used to, for example, optimize thereturn loss (magnitude of S₁₁) for the expected load.

In one embodiment of the invention, an antenna is optimized to maintainthe power coupled into the antenna with a return of −10 dB or betterover an optimal frequency band. An optimal bandwidth may be, forexample, approximately 0.25 GHz (0.125 GHz on either side of the centerfrequency), at frequencies of interest, such as, for example, 5.8 GHz.An optimal bandwidth may be, for example, approximately 1.0 GHz (0.5 GHzon either side of the center frequency), at frequencies of interest,such as, for example, 5.8 GHz.

Dielectric Filler

In embodiments of the invention, dielectric filler may have a dielectricconstant of approximately 10. In embodiments of the invention,dielectric filler may have a dielectric constant of betweenapproximately 9.7 and 10.3. In embodiments of the invention, dielectricfiller may be impervious to fluid, including cooling fluid in coolingchamber. In embodiments of the invention, dielectric filler may beconfigured to prevent liquid from entering waveguide tubing. Inembodiments of the invention, dielectric filler may be configured toefficiently couple energy from an antenna feed into tissue. Inembodiments of the invention, dielectric filler may be configured tomatch a waveguide tubing, coolant chamber, including cooling fluid andskin at a predetermined frequency of, for example frequencies in therange of: between approximately 4 GHz and 10 GHz; between approximately5 GHz and 6.5 GHZ; or frequencies of approximately 5.8 GHz. Inembodiments of the invention, dielectric filler may be configured togenerate a field having minimal electric field perpendicular to a tissuesurface. In embodiments of the invention, dielectric filler may beconfigured to generate a TE, TE₁₀, or TEM field in target tissuefrequencies in the range of: between approximately 4 GHz and 10 GHz;between approximately 5 GHz and 6.5 GHZ; or frequencies of approximately5.8 GHz.

In one embodiment of the invention, a waveguide fabricated using a crosssectional inner geometry, such as, for example, the cross-sectionalinner geometry of a WR62 waveguide tube, having a width of 15.8millimeters and a height of 7.9 millimeters is optimized at apredetermined frequency by selecting an appropriate dielectric filler.In one embodiment of the invention, an antenna, such as a waveguideantenna fabricated using a WR62 waveguide tube, is optimized at apredetermined frequency by selecting an appropriate filler material. Inone embodiment of the invention, an antenna, such as a waveguide antennafabricated using a wr62 waveguide tube, is optimized at a predeterminedfrequency by selecting a filler material having a dielectric constant inthe range of between 3 and 12. In one embodiment of the invention, anantenna, such as a waveguide antenna fabricated using a wr62 waveguidetube, is optimized at a predetermined frequency by selecting a fillermaterial having a dielectric constant of approximately 10. In oneembodiment of the invention, an antenna, such as a waveguide antennafabricated using a wr62 waveguide tube, is optimized at a predeterminedfrequency by selecting a dielectric filler material which is imperviousto fluids, such as, for example cooling fluids. In one embodiment of theinvention, an antenna, such as a waveguide antenna fabricated using awr62 waveguide tube, is optimized at a predetermined frequency byselecting a dielectric filler material which is, for example, Eccostock.In one embodiment of the invention, an antenna, may be optimized at apredetermined frequency by selecting a dielectric filler material whichis, for example, polycarbonate, Teflon, plastic or air.

Field Spreader

In one embodiment of the invention, an antenna may include a dielectricelement, which may be referred to as a field spreader, at the antennaoutput that perturbs or scatters the microwave signal in such a way thatthe E-field is applied to tissue over a wider area. In one embodiment ofthe invention, the field spreader causes the E-field to diverge as itexits the antenna. In one embodiment of the invention, a field spreadermay have a dielectric constant of between 1 and 80. In one embodiment ofthe invention, a field spreader may have a dielectric constant ofbetween 1 and 15. In embodiments of the invention, field spreaders maybe used to, for example, spread and flatten peak SAR regions, peaktemperature regions or peak power loss density regions in tissue. Inembodiments of the invention, field spreaders may be used to, forexample, spread and flatten lesions in tissue.

In one embodiment of the invention, a field spreader may be a dielectricelement. In one embodiment of the invention, a field spreader may beconfigured to spread an E-field. In one embodiment of the invention, afield spreader may be configured to extend from an output of an antennato a cooling plate. In one embodiment of the invention, a field spreadermay be configured to extend from a dielectric filler to a cooling plate.In one embodiment of the invention, a field spreader may be positionedat least partially in a cooling chamber. In one embodiment of theinvention, a field spreader may be positioned at least partially in acooling fluid. In one embodiment of the invention, a field spreader maybe configured to have rounded features. In one embodiment of theinvention, a field spreader may be oval. In one embodiment of theinvention, a field spreader positioned at least partially in a coolingfluid may have a contoured shape. In one embodiment of the invention, afield spreader positioned at least partially in a cooling fluid may beconfigured to prevent eddy currents in the cooling fluid. In oneembodiment of the invention, a field spreader positioned at leastpartially in a cooling fluid may be configured to prevent air bubblesfrom forming in the cooling fluid. In one embodiment of the invention, asystem may have multiple field spreaders.

In one embodiment of the invention, a field spreader may be configuredto have a dielectric constant which matches a dielectric filler. In oneembodiment of the invention, a field spreader may be configured to havea dielectric constant which differs from a dielectric filler. In oneembodiment of the invention, a field spreader may be configured toincrease the effective field size (EFS) by reducing field strength inthe center of a waveguide. In one embodiment of the invention, fieldspreader may be configured to increase the ratio of 50% SAR contour areaat depth in a cross section of the target tissue compared to the surfacearea of the radiating aperture by, for example, reducing field strengthin center of a waveguide. In one embodiment of the invention, fieldspreader may be configured to increase the lateral size of 50% SARcontour area at depth in a cross section of in the target tissuecompared to the surface area of the radiating aperture by, for example,reducing field strength in the center of a waveguide. In one embodimentof the invention, a field spreader may be configured to cause a signalemitted from an antenna to diverge around the field spreader creatinglocal E-field peaks that re-combine. In one embodiment of the invention,a field spreader may be configured to cause a signal emitted from anantenna to diverge around the field spreader creating local E-fieldpeaks that re-combine to form larger peak power loss density, SAR ortissue temperature regions in adjacent tissue. In one embodiment of theinvention, a field spreader may be configured to cause a signal emittedfrom an antenna to diverge around the field spreader creating localE-field peaks that re-combine to laterally enlarge lesions in adjacenttissue. In one embodiment of the invention, a field spreader may beconfigured to cause a signal emitted from an antenna to diverge aroundthe field spreader creating local E-field peaks that re-combine to formlaterally enlarged peak power loss density, SAR or tissue temperatureregions in adjacent tissue. In one embodiment of the invention, a fieldspreader may be configured to cause a signal emitted from an antenna todiverge around the field spreader creating local E-field peaks thatre-combine to form laterally enlarged lesions in adjacent tissue. In oneembodiment of the invention, a field spreader may have a cross sectionalwhich is between approximately two percent and 50 percent of the innerface of a waveguide antenna. In one embodiment of the invention, thefield spreader may have a rectangular cross section. In one embodimentof the invention, the field spreader may have a rectangular crosssection of 6 millimeters by 10 millimeters. In one embodiment of theinvention, the field spreader may have a rectangular cross section of 6millimeters by 10 millimeters when used with a waveguide having an innerface of 15.8 millimeters by 7.9 millimeters. In one embodiment of theinvention, a field spreader may have a rectangular cross section ofapproximately 60 square millimeters. In one embodiment of the invention,afield spreader may have a rectangular cross section of approximately 60square millimeters when used with a waveguide having an inner face withan area of approximately 124 square millimeters. In one embodiment ofthe invention, the field spreader may be comprised of, for example,alumina, having a dielectric constant of, for example 10. In oneembodiment of the invention, a field spreader may be configured toconsist of a dielectric region embedded in a waveguide. In oneembodiment of the invention, a field spreader may be configured toconsist of a dielectric region positioned in a cooling chamber. In oneembodiment of the invention, a field spreader may be configured toconsist of a notch in dielectric filler. In one embodiment of theinvention, a field spreader may be configured to consist of a notch indielectric filler which is configured to allow cooling fluid, such as,for example, water to flow in the notch. In one embodiment of theinvention, a field spreader may be configured to consist of coolingfluid. In one embodiment of the invention, a field spreader may beconfigured to consist of one or more air gaps. In one embodiment of theinvention, a field spreader may be positioned in the center of anaperture of an adjacent antenna. In one embodiment of the invention, afield spreader may comprise multiple field spreaders. In one embodimentof the invention, a field spreader may have a racetrack or ovoid shape.In one embodiment of the invention, a field spreader may have aracetrack shape and a length of, for example, 7 millimeters. In oneembodiment of the invention, a field spreader may have a racetrack shapeand a width of, for example, 4 millimeters.

Efficiency/Fringing

In one embodiment of the invention, an antenna, such as, for example, awaveguide antenna, is optimized to reduce or eliminate free spaceradiation due to fringing fields. In one embodiment of the invention, anantenna, such as, for example, a waveguide antenna, is optimized toredirect fringing fields towards tissue. In one embodiment of theinvention, an antenna, such as, for example, a waveguide antenna isoptimized to improve the efficiency of the antenna, which efficiency maybe measured by, for example comparing the energy available at the inputof the antenna to the energy which is coupled into adjacent tissue. Inone embodiment of the invention, an antenna, such as, for example, awaveguide antenna is optimized to improve the efficiency of the antennasuch that at least seventy percent of the energy available at the inputof the antenna is deposited in tissue adjacent to an output of theantenna. In one embodiment of the invention, an antenna, such as, forexample, a waveguide antenna, may be optimized by positioning the outputof the antenna such that at least an outer edge of the waveguide tube ofthe waveguide antenna is in contact with fluid. In one embodiment of theinvention, an antenna, such as, for example, a waveguide antenna, may beoptimized by positioning the output of the antenna such that the outputof the antenna is in contact with fluid. In one embodiment of theinvention, an antenna, such as, for example, a waveguide antenna, may beoptimized by positioning the output of the antenna such that an outputof the antenna is covered by an insulator which separates the outputfrom a fluid, the insulator having a thickness which reduces the freespace radiation due to the fringing fields at the output of thewaveguide. In one embodiment of the invention, an antenna, such as, forexample, a waveguide antenna, may be optimized by positioning the outputof the antenna such that an output of the antenna is covered by aninsulator which separates the output from a fluid, such as, for example,a cooling fluid the insulator having a thickness of less than 0.005″. Inone embodiment of the invention power transfer from an antenna, such as,for example, a waveguide antenna, through a cooling fluid and intoadjacent tissue is optimized by reducing the thickness of an isolationlayer between the output of the antenna and the cooling fluid. In oneembodiment of the invention power transfer from an antenna, such as, forexample, a waveguide antenna, through a cooling fluid and into adjacenttissue is optimized by placing the output of the antenna into thecooling fluid. In one embodiment of the invention an antenna, such as,for example, a waveguide antenna, may be optimized by covering theoutput of the antenna with an insulator, such as, for example,polycarbonate having a dielectric constant which is less than adielectric constant of an antenna filler material. In one embodiment ofthe invention an antenna, such as, for example, a waveguide antenna, maybe optimized by covering the output of the antenna with an insulator,such as, for example, polycarbonate having a dielectric constant whichis less than a dielectric constant of an antenna filler material, thethickness of the insulator being between approximately 0.0001″ and0.006″. In one embodiment of the invention an antenna, such as, forexample, a waveguide antenna, may be optimized by covering the output ofthe antenna with an insulator the thickness of the insulator beingbetween approximately 0.015″. In one embodiment of the invention anantenna, such as, for example, a waveguide antenna, may be optimized bycovering the output of the antenna with an insulator, such as, forexample, polycarbonate having a dielectric constant which is less than adielectric constant of an antenna filler material, the thickness of theinsulator being between approximately 0.0001″ and 0.004″. In oneembodiment of the invention an antenna, such as, for example, awaveguide antenna, may be optimized by covering the output of theantenna with an insulator, such as, for example, polycarbonate having adielectric constant which is less than a dielectric constant of anantenna filler material, the thickness of the insulator is approximately0.002″. In one embodiment of the invention an antenna, such as, forexample, a waveguide antenna, may be optimized by covering the output ofthe antenna with an insulator, such as, for example, alumina having adielectric constant which is substantially equal to the dielectricconstant of an antenna filler material.

Polarization

In one embodiment of the invention, an antenna may be optimized by, forexample, optimizing the design of the antenna to ensure that the antennaradiates in a TE mode. In one embodiment of the invention, an antennamay be optimized by, for example, optimizing the design of the antennato ensure that the antenna radiates in a TEM mode. In one embodiment ofthe invention, an antenna, such as, for example, a waveguide antenna maybe optimized by, for example, optimizing the design of the antenna toensure that the antenna radiates in a substantially pure TE₁₀ mode.

Cooling System

In one embodiment of the invention, a cooling system is placed between adevice adapted to emit electromagnetic radiation and skin. In oneembodiment of the invention, a cooling system includes a cooling fluidand a cooling plate. In one embodiment of the invention, a coolingsystem includes a cooling fluid flowing past a cooling plate. In oneembodiment of the invention, a cooling fluid flows through a coolingchamber. In one embodiment of the invention, a cooling fluid flowsthrough a cooling chamber which is positioned between a device adaptedto emit electromagnetic radiation and a cooling plate. In one embodimentof the invention, a cooling system includes a tissue interface. In oneembodiment of the invention, a cooling system may be incorporated into atissue head. Other cooling systems and various components that may beused with systems and devices described herein are described andillustrated, for example, at FIGS. 33-36 and pp. 40-45 of U.S.Provisional App. No. 60/912,899; and FIGS. 11A-11B and pp. 21-24 of U.S.Provisional App. No. 61/013,274 both incorporated by reference in theirentireties, as well as illustrated and described, for example, in FIGS.33-36 and pp. 42-46 of Appendix 1 and FIGS. 11A-11B and pp. 27-29 ofAppendix 2.

Temperature

In one embodiment of the invention, a cooling system is optimized tomaintain skin surface at a predetermined temperature. In one embodimentof the invention, a cooling system is optimized to maintain skin surfaceat a temperature of less than 45° C. In one embodiment of the invention,a cooling system is optimized to maintain skin surface at a temperatureof less than 40° C. In one embodiment of the invention, a cooling systemis optimized to maintain skin surface at a temperature of approximately22° C. In one embodiment of the invention, a cooling system is optimizedto maintain a cooling plate at a temperature of less than 40° C. In oneembodiment of the invention, a cooling system is optimized to maintainskin surface at a temperature of less than 45° C. In one embodiment ofthe invention, cooling fluid is used remove heat from the coolingsystem.

Cooling Fluid

In one embodiment of the invention, moving cooling fluid is used toremove heat from the cooling system. In one embodiment of the invention,cooling fluid has a temperature of between −5° C. and 40° C. as itenters a cooling chamber in the cooling system. In one embodiment of theinvention, cooling fluid has a temperature of between 10 and 25° C. asit enters a cooling chamber in the cooling system. In one embodiment ofthe invention, cooling fluid has a temperature of approximately 22° C.as it enters a cooling chamber in the cooling system. In one embodimentof the invention, cooling fluid has a flow rate of at least 100milliliters per second as it moves through a cooling chamber. In oneembodiment of the invention, cooling fluid has a flow rate of between250 and 450 milliliters per second as it moves through a coolingchamber. In one embodiment of the invention, cooling fluid has avelocity of between 0.18 and 0.32 meters per second as it moves througha cooling chamber. In one embodiment of the invention, coolant flow in acooling chamber is non-laminar In one embodiment of the invention,coolant flow in a cooling chamber is turbulent to facilitate heattransfer. In one embodiment of the invention, cooling fluid has aReynolds number of between approximately 1232 and 2057 prior to enteringa cooling chamber. In one embodiment of the invention, cooling fluid hasa Reynolds number of between approximately 5144 and 9256 prior toentering a cooling chamber.

In one embodiment of the invention, cooling fluid is optimized to besubstantially transparent to microwave energy. In one embodiment of theinvention, cooling fluid is optimized to minimize absorption ofelectromagnetic energy. In one embodiment of the invention, coolingfluid is optimized to match an antenna to tissue. In one embodiment ofthe invention, cooling fluid is optimized to facilitate the efficienttransfer of microwave energy to tissue. In one embodiment of theinvention, cooling fluid is optimized to conduct heat away from thesurface of skin. In one embodiment of the invention, cooling fluid iscomprised of a fluid having a high dielectric constant. In oneembodiment of the invention, a cooling fluid is optimized to have a highdielectric constant of between 70 and 90. In one embodiment of theinvention, a cooling fluid is optimized to have a high dielectricconstant of approximately 80. In one embodiment of the invention, acooling fluid is optimized to have a low dielectric constant of between2 and 10. In one embodiment of the invention, a cooling fluid isoptimized to have a low dielectric constant of approximately 2. In oneembodiment of the invention, a cooling fluid is optimized to have adielectric constant of approximately 80. In one embodiment of theinvention, cooling fluid is comprised, at least in part, of de-ionizedwater. In one embodiment of the invention, cooling fluid is comprised,at least in part, of alcohol. In one embodiment of the invention,cooling fluid is comprised, at least in part, of ethylene glycol. In oneembodiment of the invention, cooling fluid is comprised, at least inpart, of glycerol. In one embodiment of the invention, cooling fluid iscomprised, at least in part, of a germicide. In one embodiment of theinvention, cooling fluid is comprised, at least in part of vegetableoil. In one embodiment of the invention, cooling fluid is comprised of afluid having a low electrical conductivity. In one embodiment of theinvention, cooling fluid is comprised of a fluid having an electricalconductivity of less than approximately 0.5 siemens per meter.

Cooling Plate

In embodiments of the invention, a cooling plate may be, for exampleconfigured to contact skin. In embodiments of the invention, a coolingplate may be, for example configured cool skin tissue. In embodiments ofthe invention, a cooling plate may be, for example configured tophysically separate skin tissue from a microwave antenna. In embodimentsof the invention, a cooling plate may be, for example configured toconform to the hair bearing region of the axilla of a human Inembodiments of the invention, a cooling plate may be, for exampleconfigured to constitute a thermoelectric cooler. In embodiments of theinvention, a cooling plate may be, for example configured to bethermally conductive. In embodiments of the invention, a cooling platemay be, for example configured to be substantially transparent tomicrowave energy. In embodiments of the invention, a cooling plate maybe, for example configured to be thin enough to minimize microwavereflection. In embodiments of the invention, a cooling plate may be, forexample configured to be composed of ceramic In embodiments of theinvention, a cooling plate may be, for example configured or to becomposed of alumina.

In one embodiment of the invention, a cooling plate is optimized toconduct electromagnetic energy to tissue. In one embodiment of theinvention, a cooling plate is optimized to conduct heat from the surfaceof skin into a cooling fluid. In one embodiment of the invention, acooling plate is optimized to have a thickness of between 0.0035″ and0.025″, and may include thickness of up to 0.225″. In one embodiment ofthe invention, a cooling plate is optimized to have a dielectricconstant of between 2 and 15. In one embodiment of the invention, acooling plate is optimized to have a dielectric constant ofapproximately 10. In one embodiment of the invention, a cooling plate isoptimized to have a low electrical conductivity. In one embodiment ofthe invention, a cooling plate is optimized to have an electricalconductivity of less than 0.5 siemens per meter. In one embodiment ofthe invention, a cooling plate is optimized to have a high thermalconductivity. In one embodiment of the invention, a cooling plate isoptimized to have a thermal conductivity of between 18 and 50 Watts permeter-Kelvin at room temperature. In one embodiment of the invention, acooling plate is optimized to have a thermal conductivity of between 10and 100 Watts per meter-Kelvin at room temperature. In one embodiment ofthe invention, a cooling plate is optimized to have a thermalconductivity of between 0.1 and 5 Watts per meter-Kelvin at roomtemperature. In one embodiment of the invention, a cooling plate iscomprised, at least in part, of a ceramic material. In one embodiment ofthe invention, a cooling plate is comprised, at least in part, ofalumina.

In one embodiment of the invention, a cooling plate may be, for example,a thin film polymer material. In one embodiment of the invention, acooling plate may be, for example, a polyimide material. In oneembodiment of the invention, a cooling plate may be, for example, amaterial having a conductivity of approximately 0.12 Watts permeter-Kelvin and a thickness of between approximately 0.002″ and 0.010″.

Cooling Chamber

In one embodiment of the invention, a cooling chamber has a thicknesswhich is optimized for the electromagnetic radiation frequency, coolingfluid composition and cooling plate composition. In one embodiment ofthe invention, a cooling chamber has a thickness which is optimized fora high dielectric cooling fluid. In one embodiment of the invention, acooling chamber has a thickness which is optimized for a cooling fluidhaving a dielectric constant of approximately 80, such as, for example,de-ionized water. In one embodiment of the invention, a cooling chamberhas a thickness of between 0.5 and 1.5 millimeters. In one embodiment ofthe invention, a cooling chamber has a thickness of approximately 1.0millimeters. In one embodiment of the invention, a cooling chamber has athickness which is optimized for a low dielectric cooling fluid. In oneembodiment of the invention, a cooling chamber has a thickness which isoptimized for a cooling fluid which has a dielectric constant ofapproximately 2, such as, for example, vegetable oil. Low dielectric,low conductivity cooling fluids may be advantageous where it isdesirable to limit the losses or to match elements. In one embodiment ofthe invention, a cooling chamber is optimized such that eddy currentsare minimized as fluid flows through the cooling chamber. In oneembodiment of the invention, a cooling chamber is optimized such thatair bubbles are minimized as fluid flows through the cooling chamber. Inone embodiment of the invention, field spreaders located in the coolingchamber are positioned and designed to optimize laminar flow of coolingfluid through the cooling chamber. In one embodiment of the invention,field spreaders located in the cooling chamber are substantially oval inshape. In one embodiment of the invention, field spreaders located inthe cooling chamber are substantially round in shape. In one embodimentof the invention, field spreaders located in the cooling chamber aresubstantially rectangular in shape.

Thermoelectric Module

In one embodiment of the invention, a cooling system optimized tomaintain the skin surface at a predetermined temperature may be, forexample a thermoelectric module. In one embodiment of the invention, acooling system is optimized to maintain the skin surface at apredetermined temperature by attaching the cold plate side of athermoelectric cooler(s) (TEC) to a face of the cooling plate adjacentto the waveguide antenna(s). The hot side of the TEC(s) is attached to afinned heat sink(s) that is acted upon by an axial fan(s) in order tomaintain the hot side of the TEC(s) at a low temperature to optimize thecooling performance of the TEC(s). The attachment of the TEC(s) to thecooling plate and heat sink(s) utilizes ceramic thermal adhesive epoxy.For example, the TEC(s) may be part number 06311-5L31-03CFL, availablefrom Custom Thermoelectric, the heat sink(s) may be part number655-53AB, available from Wakefield Engineering, the ceramic thermaladhesive epoxy may be available from Arctic Silver and the axial fans(s)may be part number 1608KL-04W-B59-L00 available from NMB-MAT.

In one embodiment of the invention, a cooling system is optimized tomaintain the skin surface at a predetermined temperature by constructingthe cold plate side of a thermoelectric cooler(s) (TEC) as the coolingplate adjacent to or surrounding the waveguide antenna(s) with anopening(s) in the hot side of the TEC(s) where the waveguide antenna(s)exist. The hot side of the TEC(s) is attached to a finned heat sink(s)that is acted upon by an axial fan(s) in order to maintain the hot sideof the TEC(s) at a low temperature to optimize the cooling performanceof the TEC(s). The attachment of the TEC(s) to the heat sink(s) utilizesceramic thermal adhesive epoxy. For example, the TEC(s) may be availablefrom Laird Technology, the heat sink(s) may be part number 655-53AB,available from Wakefield Engineering, the ceramic thermal adhesive epoxymay be available from Arctic Silver and the axial fans(s) may be partnumber 1608KL-04W-B59-L00 available from NMB-MAT.

In one embodiment of the invention, a cooling system is optimized tomaintain the skin surface at a predetermined temperature by attachingthe cold plate side of a thermoelectric cooler(s) (TEC) to a side(s) ofthe waveguide antenna(s). The hot side of the TEC(s) is attached to afinned heat sink(s) that is acted upon by an axial fan(s) in order tomaintain the hot side of the TEC(s) at a low temperature to optimize thecooling performance of the TEC(s). The attachment of the TEC(s) to thewaveguide antenna(s) and heat sink(s) utilizes ceramic thermal adhesiveepoxy. For example, the TEC(s) may be part number 06311-5L31-03CFL,available from Custom Thermoelectric, the heat sink(s) may be partnumber 655-53AB, available from Wakefield Engineering, the ceramicthermal adhesive epoxy may be available from Arctic Silver and the axialfans(s) may be part number 1608KL-04W-B59-L00 available from NMB-MAT.

Energy

In one embodiment of the invention, energy is delivered to the skin fora period of time which optimizes the desired tissue effect. In oneembodiment of the invention, energy is delivered to the skin for aperiod of between 3 and 4 seconds. In one embodiment of the invention,energy is delivered to the skin for a period of between 1 and 6 seconds.In one embodiment of the invention, energy is delivered to a targetregion in tissue. In one embodiment of the invention energy delivered tothe target region for a time sufficient to result in an energy densityat the target tissue of between 0.1 and 0.2 Joules per cubic millimeter.In one embodiment of the invention energy delivered to the target regionfor a time sufficient to heat the target tissue to a temperature of atleast 75° C. In one embodiment of the invention energy delivered to thetarget region for a time sufficient to heat the target tissue to atemperature of between 55 and 75° C. In one embodiment of the inventionenergy delivered to the target region for a time sufficient to heat thetarget tissue to a temperature of at least 45° C.

Cooling

In one embodiment of the invention, the skin surface is cooled for aperiod of time which optimizes the desired tissue effect. In oneembodiment of the invention, the skin surface is cooled during the timeenergy is delivered to the skin. In one embodiment of the invention, theskin surface is cooled for a period of time prior to the time energy isdelivered to the skin. In one embodiment of the invention, the skinsurface is cooled for a period of between 1 and 5 seconds prior to thetime energy is delivered to the skin. In one embodiment of theinvention, the skin surface is cooled for a period of approximately 2seconds prior to the time energy is delivered to the skin. In oneembodiment of the invention, the skin surface is cooled for a period oftime after to the time energy is delivered to the skin. In oneembodiment of the invention, the skin surface is cooled for a period ofbetween 10 and 20 seconds after the time energy is delivered to theskin. In one embodiment of the invention, the skin surface is cooled fora period of approximately 20 seconds after the time energy is deliveredto the skin.

Output Power

In one embodiment of the invention, power is delivered to a deviceadapted to radiate electromagnetic energy. In one embodiment of theinvention, power is delivered to an input to an antenna, such as, forexample, the feed to a waveguide antenna. In one embodiment of theinvention, the power available at the antenna's input port is between 50and 65 Watts. In one embodiment of the invention, the power available atthe antenna's input port is between 40 and 70 Watts. In one embodimentof the invention, power available at the antenna's input port variesover time.

Tissue Acquisition

In one embodiment of the invention, skin is held in an optimal positionwith respect to an energy delivery device. In one embodiment of theinvention, skin is held in an optimal position with respect to an energydelivery device using vacuum pressure. In one embodiment of theinvention, skin is held in an optimal position with respect to an energydelivery device using vacuum pressure of between 400 and 750 millimetersof mercury. In one embodiment of the invention, skin is held in anoptimal position with respect to an energy delivery device using vacuumpressure of approximately 650 millimeters of mercury. Other tissueacquisition systems, methods, and devices that can be used withembodiments of the invention to hold the skin in place and/or protectnon-target tissue structures can be found, for example, at FIGS. 38-52Cand pp. 46-57 of U.S. Provisional App. No. 60/912,899; and FIGS. 12-16Band pp. 24-29 of U.S. Provisional App. No. 61/013,274 both incorporatedby reference in their entireties, as well as illustrated and described,for example, in FIGS. 38-52C and pp. 46-55 of Appendix 1 and FIGS.12-16B and pp. 29-33 of Appendix 2.

Tissue Interface Tissue Chamber

In one embodiment of the invention, a tissue chamber may be, forexample, a suction chamber. In one embodiment of the invention, a tissuechamber may be configured to acquire at least a portion of the skintissue. In one embodiment of the invention, a tissue chamber may beoperatively coupled to a vacuum source. In one embodiment of theinvention, a tissue chamber may be configured with at least one taperedwall. In one embodiment of the invention, a tissue chamber may beconfigured to at least partially acquire skin tissue and bring skintissue in contact with cooling plate. In one embodiment of theinvention, tissue chamber may be configured to include at least onesuction element. In one embodiment of the invention, tissue chamber maybe configured to elevate skin and placing skin in contact with a coolingelement. In one embodiment of the invention, tissue chamber may beconfigured to elevate skin and placing skin in contact with a coolingelement. In one embodiment of the invention, tissue chamber may beconfigured to elevate skin and placing skin in contact with a suctionchamber. In one embodiment of the invention, tissue chamber may beconfigured to elevate skin and placing skin in contact with suctionopenings. In one embodiment of the invention, suction openings mayinclude at least one channel wherein the channel may have rounded edges.In one embodiment of the invention, tissue chamber may have an ovoid orracetrack shape wherein the tissue chamber includes straight edgesperpendicular to direction of cooling fluid flow. In one embodiment ofthe invention, tissue chamber may be configured to elevate skinseparating skin tissue from underlying muscle tissue. In one embodimentof the invention, tissue chamber may be configured to include at leastone temperature sensor. In one embodiment of the invention, tissuechamber may be configured to include at least one temperature sensorwherein the temperature sensor may be a thermocouple. In one embodimentof the invention, tissue chamber may be configured to include at leastone temperature sensor wherein the temperature sensor is configured tomonitor the temperature at skin surface. In one embodiment of theinvention, tissue chamber may be configured to include at least onetemperature sensor wherein the temperature sensor is configured suchthat it does not significantly perturb a microwave signal.

In one embodiment of the invention, a tissue interface may comprise atissue chamber which is optimized to separate skin from underlyingmuscle. In one embodiment of the invention, a tissue interface maycomprise a vacuum chamber which is optimized to separate skin fromunderlying muscle when skin is pulled into a tissue chamber by, forexample, vacuum pressure. In one embodiment of the invention, a tissuechamber may be optimized to have a depth of between approximately 1millimeter and approximately 30 millimeters. In one embodiment of theinvention, a tissue chamber may be optimized to have a depth ofapproximately 7.5 millimeters. In one embodiment of the invention, wallsof a tissue chamber may be optimized to have an angle of betweenapproximately 2 and 45 degrees. In one embodiment of the invention,walls of a tissue chamber may be optimized to have a chamber angle Z ofbetween approximately 5 and 20 degrees. In one embodiment of theinvention, walls of a tissue chamber may be optimized to have a chamberangle Z of approximately 20°. In one embodiment of the invention, atissue chamber may be optimized to have an ovoid shape. In oneembodiment of the invention, a tissue chamber may be optimized to have aracetrack shape. In one embodiment of the invention, a tissue chambermay be optimized to have an aspect ratio wherein the aspect ratio may bedefined as the minimum dimension of a tissue interface surface to theheight of the vacuum chamber. In the embodiment of the inventionillustrated in FIG. 8, the aspect ratio may be, for example the ratiobetween minimum dimension 10 and tissue depth Y. In one embodiment ofthe invention, a tissue chamber may be optimized to have an aspect ratioof between approximately 1:1 and approximately 3:1. In one embodiment ofthe invention, a tissue chamber may be optimized to have an aspect ratioof approximately 2:1.

Staged Treatments

In some embodiments, it may be desirable to perform the treatment instages. Additionally, the treatment may be patterned such that sectionsof target tissue are treated in the initial stage while other sectionsare treated in subsequent stages. Treatments using systems and devicesdisclosed herein may, for example, be treated in stages as disclosed in,for example, at FIGS. 54-57 and pp. 61-63 of U.S. Provisional App. No.60/912,899; and FIGS. 17-19 and pp. 32-34 of U.S. Provisional App. No.61/013,274 both incorporated by reference in their entireties, as wellas illustrated and described, for example, in FIGS. 54-57 and pp. 58-60of Appendix 1 and FIGS. 17-19 and pp. 36-38 of Appendix 2.

Diagnosis

Embodiments of the present invention also include methods andapparatuses for identifying and diagnosing patients with hyperhidrosis.Such diagnosis can be made based on subjective patient data (e.g.,patient responses to questions regarding observed sweating) or objectivetesting. In one embodiment of objective testing, an iodine solution canbe applied to the patient to identify where on a skin surface a patientis sweating and not sweating. Moreover, particular patients can bediagnosed based on excessive sweating in different parts of the body inorder to specifically identify which areas to be treated. Accordingly,the treatment may be applied only selectively to different parts of thebody requiring treatment, including, for example, selectively in thehands, armpits, feet and/or face.

Quantifying Treatment Success

Following completion of any of the treatments described above, or anystage of a treatment, the success can be evaluated qualitatively by thepatient, or may be evaluated quantitatively by any number of ways. Forexample, a measurement can be taken of the number of sweat glandsdisabled or destroyed per surface area treated. Such evaluation could beperformed by imaging the treated area or by determining the amount oftreatment administered to the treated area (e.g., the quantity of energydelivered, the measured temperature of the target tissue, etc.). Theaforementioned iodine solution test may also be employed to determinethe extent of treatment effect. In addition, a treatment can beinitiated or modified such that the amount of sweating experienced by apatient may be reduced by a desired percentage as compared topre-treatment under defined testing criteria. For example, for a patientdiagnosed with a particularly severe case of hyperhidrosis, the amountof sweating may be reduced by about 10%, 20%, 30%, 40%, 50%, 60%, 70%,80%, 90% or more. For a patient diagnosed with a less severe or morenormal sweating profile, a step-wise reduction of sweating may beachieved, but with less resolution. For example, such a patient may onlybe able to achieve partial anhidrosis in 25% increments.

Overview of Systems, Methods, and Devices

In one embodiment of the invention, a method of applying energy totissue is described. In one embodiment of the invention, the methodincludes the step of generating a radiation pattern with a region oflocalized high power loss density in skin. In one embodiment of theinvention, the method includes the step of generating a radiationpattern with a region of localized high power loss density in a regionof the dermis adjacent a critical interface. In one embodiment of theinvention, the method includes the step of generating a radiationpattern with a region of localized high power loss density in aglandular layer. In one embodiment of the invention, the method includesthe step of generating a radiation pattern in skin with first and secondregions of localized high power loss density wherein the first andsecond regions are separated by a region of low power loss density. Inone embodiment of the invention, the method includes the step ofgenerating a radiation pattern with a plurality of regions of localizedhigh power loss density in skin wherein the first and second regions areseparated by a region of low power loss density. In one embodiment ofthe invention, the method includes the step of generating a radiationpattern with a plurality of regions of localized high power loss densityin skin wherein adjacent regions of high power loss density areseparated by regions of low power loss density.

In one embodiment of the invention, a method of applying energy totissue is described. In one embodiment of the invention, the methodincludes the step of generating a radiation pattern with a region oflocalized high specific absorption rate (SAR) in skin. In one embodimentof the invention, the method includes the step of generating a radiationpattern with a region of localized high specific absorption rate (SAR)in a region of the dermis adjacent a critical interface. In oneembodiment of the invention, the method includes the step of generatinga radiation pattern with a region of localized high specific absorptionrate (SAR) in a glandular layer. In one embodiment of the invention, themethod includes the step of generating a radiation pattern in skin withfirst and second regions of localized specific absorption rate (SAR)wherein the first and second regions are separated by a region of lowspecific absorption rate (SAR). In one embodiment of the invention, themethod includes the step of generating a radiation pattern with aplurality of regions of localized high specific absorption rate (SAR) inskin wherein the first and second regions are separated by a region oflow specific absorption rate (SAR). In one embodiment of the invention,the method includes the step of generating a radiation pattern with aplurality of regions of localized specific absorption rate (SAR) in skinwherein adjacent regions of high specific absorption rate (SAR) areseparated by regions of low specific absorption rate (SAR).

In one embodiment of the invention, a method of applying energy totissue is described. In one embodiment of the invention, the methodincludes the step of generating a radiation pattern with a region oflocalized high temperature in skin. In one embodiment of the invention,the method includes the step of generating a radiation pattern with aregion of localized high temperature in a region of the dermis adjacenta critical interface. In one embodiment of the invention, the methodincludes the step of generating a radiation pattern with a region oflocalized high temperature in a glandular layer. In one embodiment ofthe invention, the method includes the step of generating a radiationpattern in skin with first and second regions of localized temperaturewherein the first and second regions are separated by a region of lowtemperature. In one embodiment of the invention, the method includes thestep of generating a radiation pattern with a plurality of regions oflocalized high temperature in skin wherein the first and second regionsare separated by a region of low temperature. In one embodiment of theinvention, the method includes the step of generating a radiationpattern with a plurality of regions of localized temperature in skinwherein adjacent regions of high temperature are separated by regions oflow temperature.

In one embodiment of the invention, a method of aligning electromagneticfield to preferentially treat tissue having a relatively high watercontent is described. In one embodiment of the invention, the methodincludes the steps of irradiating tissue with an electromagneticElectric field aligned with a surface of the skin. In one embodiment ofthe invention, the method includes irradiating tissue withelectromagnetic radiation in the TE₁₀ mode. In one embodiment of theinvention, the method includes irradiating tissue with electromagneticradiation having a minimal E-field in a direction perpendicular to atleast a portion of a skin surface. In one embodiment of the invention,the method includes aligning an E-field component of an electromagneticwave to preferentially heat tissue having a high water content byirradiating with transverse electric (TE) or transverse electromagnetic(TEM) waves.

In one embodiment of the invention, a method for controlling thedelivery of energy to tissue is described. In one embodiment of theinvention, the method of delivering energy includes the step ofdelivering energy at a frequency of approximately 5.8 GHz. In oneembodiment of the invention, the method of delivering energy includesthe step of delivering energy having a power of greater thanapproximately 40 Watts. In one embodiment of the invention, the methodof delivering energy includes the step of delivering energy for a periodof between approximately 2 seconds and approximately 10 seconds. In oneembodiment of the invention, the method of delivering energy includesthe step of pre-cooling skin surface for a period of approximately 2seconds. In one embodiment of the invention, the method of deliveringenergy includes the step of post cooling for a period of approximately20 seconds. In one embodiment of the invention, the method of deliveringenergy includes the step of maintaining tissue engagement for a periodof more than approximately 22 seconds. In one embodiment of theinvention, the method of delivering energy includes the step of engagingtissue using a vacuum pressure of approximately 600 millimeters ofmercury. In one embodiment of the invention, the method of deliveringenergy includes the step of measuring skin temperature. In oneembodiment of the invention, the method of delivering energy includesthe step of adjusting energy delivery duration; pre-cooling duration;post-cooling duration; output power; frequency; vacuum pressure as aresult of feedback of tissue parameters such as, for example, skintemperature. In one embodiment of the invention, the method ofdelivering energy includes the step of adjusting energy deliveryduration; pre-cooling duration; post-cooling duration; output power;frequency; vacuum pressure as a result of feedback of tissue parameterssuch as, for example, cooling fluid temperature.

In one embodiment of the invention, a method of removing heat fromtissue is described. In one embodiment of the invention, a method ofcooling tissue is described, the method including engaging the surfaceof the skin. In one embodiment of the invention, the method includes thestep of positioning a cooling element in contact with the skin surface.In one embodiment of the invention, the method includes the step ofconductively cooling the skin surface. In one embodiment of theinvention, the method includes the step of convectively cooling the skinsurface. In one embodiment of the invention, the method includes thestep of conductively and convectively cooling the skin surface

In one embodiment of the invention, a method of damaging or destroyingtissue structures is described. In one embodiment of the invention, amethod of damaging or destroying glands is described. In one embodimentof the invention the method includes the step of inducing hyperthermiain the tissue structures. In one embodiment of the invention,hyperthermia may be accomplished by mild heating of tissue to atemperature of, for example, between approximately 42° C. and 45° C. Inone embodiment of the invention the method includes the step of ablatingtissue structures may be accomplished by heating of tissue totemperatures in excess of approximately 47° C.

In one embodiment of the invention a method of treating tissue usingelectromagnetic radiation is described. In one embodiment of theinvention a method of treating tissue includes creating a secondaryeffect in tissue. In one embodiment of the invention a method oftreating tissue includes creating a secondary effect in tissue whereinthe secondary effect includes, for example, reducing bacterialcolonization. In one embodiment of the invention a method of treatingtissue includes creating a secondary effect in tissue wherein thesecondary effect includes clearing or reducing skin blemishes. In oneembodiment of the invention a method of treating tissue includescreating a secondary effect in tissue wherein the secondary effectincludes clearing or reducing skin blemishes resulting from, forexample, acne vulgaris. In one embodiment of the invention a method oftreating tissue includes damaging sebaceous glands. In one embodiment ofthe invention a method of treating tissue includes disabling sebaceousglands. In one embodiment of the invention a method of treating tissueincludes temporarily disabling sebaceous glands.

In one embodiment of the invention, a method of delivering energy toselected tissue is described. In one embodiment of the invention, themethod includes delivering energy via a microwave energy deliveryapplicator. In one embodiment of the invention, the method involvesdelivering energy sufficient to create a thermal effect in a targettissue within the skin tissue. In one embodiment of the invention, themethod includes the step of delivering energy to tissue which is subjectto dielectric heating. In one embodiment of the invention, the methodincludes the step of delivering energy to tissue having a highdielectric moment. In one embodiment of the invention, the methodincludes delivering energy to target tissue within the skin tissueselected from the group consisting of collagen, hair follicles,cellulite, eccrine glands, apocrine glands, sebaceous glands, spiderveins and combinations thereof. In one embodiment of the invention,target tissue within the skin tissue comprises the interface between thedermal layer and subcutaneous layer of the skin tissue. In oneembodiment of the invention, creating a thermal effect in the targettissue comprises thermal alteration of at least one sweat gland. In oneembodiment of the invention, creating a thermal effect in the targettissue comprises ablation of at least one sweat gland.

In one embodiment of the invention, a method of delivering microwaveenergy to tissue is described. In one embodiment of the invention, themethod includes the step of applying a cooling element to the skintissue. In one embodiment of the invention, the method includes the stepof applying microwave energy to tissue at a power, frequency andduration and applying cooling at a temperature and a duration sufficientto create a lesion proximate interface between the dermis layer andsubcutaneous layer in the skin tissue while minimizing thermalalteration to non-target tissue in the epidermis and dermis layers ofthe skin tissue. In one embodiment of the invention, the method includesthe step of applying microwave energy to a second layer of skincontaining sweat glands sufficient to thermally alter the sweat glands.In one embodiment of the invention, the method includes the step ofapplying microwave energy while the first layer of skin is protectivelycooled, the second layer being deeper than the first layer relative tothe skin surface. In one embodiment of the invention, the methodincludes the step of cooling via a cooling element.

In one embodiment of the invention, the method includes the step ofusing one or more field spreaders to spread the MW energy as it emergesfrom an antenna. In one embodiment of the invention, the method includescreating a contiguous lesion larger than a single waveguide lesion. Inone embodiment of the invention, the method includes the step of usingmultiple antennas. In one embodiment of the invention, the methodincludes the step of creating a contiguous lesion larger than a singlewaveguide lesion. In one embodiment of the invention, the methodincludes the step of using an array of waveguides. In one embodiment ofthe invention, the method includes the step of activating a plurality ofwaveguides in series. In one embodiment of the invention, the methodincludes the step of activating multiple antennas. In one embodiment ofthe invention, the method includes the step of activating less than allantennas in an array. In one embodiment of the invention, the methodincludes the step of continuously cooling under all antennas in anarray.

In one embodiment of the invention, a method of applying energy totissue is described. In one embodiment of the invention, the methodincludes the step of applying energy at a depth deeper than a skinsurface. In one embodiment of the invention, the method includes thestep of applying energy but not as deep as nerve or muscle tissue. Inone embodiment of the invention, the method includes the step ofapplying electromagnetic radiation at a frequency which concentratesenergy at target tissue

In one embodiment of the invention, a method of selectively heatingtissue is described. In one embodiment of the invention, the methodincludes the step of selectively heating tissue by dielectric heating.In one embodiment of the invention, the method includes the step ofselectively heating glands. In one embodiment of the invention, themethod includes the step of selectively heating glandular fluid. In oneembodiment of the invention, the method includes the step of heatingtissue to a temperature sufficient to damage a gland. In one embodimentof the invention, the method includes the step of heating the gland to atemperature sufficient to result in morbidity. In one embodiment of theinvention, the method includes the step of heating the gland to atemperature sufficient to result in death. In one embodiment of theinvention, the method includes the step of heating the gland to atemperature sufficient to damage adjacent hair follicles. In oneembodiment of the invention, the method includes the step of heating thegland to a temperature sufficient to destroy adjacent hair follicles. Inone embodiment of the invention, the method includes the step of heatingthe gland to a temperature sufficient to induce hyperthermia in tissueat the skin/fat interface. In one embodiment of the invention, themethod includes the step of heating the gland to a temperaturesufficient to induce hyperthermia in tissue at the skin/fat interfacewhile minimizing hyperthermia in surrounding tissue. In one embodimentof the invention, the method includes the step of heating the gland toat least 50° C.

In one embodiment of the invention, a method of generating a temperatureprofile in skin tissue is described. In one embodiment of the inventionthe method includes generating a temperature profile having a peak inregion directly above skin-fat interface. In one embodiment of theinvention, the method includes the step of generating a temperatureprofile wherein the temperature declines towards the skin surface. Inone embodiment of the invention, the method includes the step ofgenerating a temperature profile wherein the temperature declinestowards the skin surface in the absence of cooling.

In one embodiment of the invention, a method of positioning skin isdescribed. In one embodiment of the invention, the method includes thestep of using suction, pinching or adhesive. In one embodiment of theinvention, the method includes the step of using suction, pinching oradhesive to lift a dermal and subdermal layer away from a muscle layer.

In one embodiment of the invention, a method of applying energy totissue is described. In one embodiment of the invention, the methodincludes the step of placing a microwave energy delivery applicator overthe skin tissue. In one embodiment of the invention, the microwaveapplicator includes a microwave antenna. In one embodiment of theinvention, the microwave antenna is selected from the group consistingof: single slot, multiple slot, waveguide, horn, printed slot, patch,Vivaldi antennas and combinations thereof. In one embodiment of theinvention, the method includes the step of positioning the microwaveenergy delivery applicator over a region having more absorptive tissueelements. In one embodiment of the invention, the method includes thestep of positioning the microwave energy delivery applicator over aregion having a concentration of sweat glands. In one embodiment of theinvention, the method includes the step of positioning the microwaveenergy delivery applicator over a hair bearing area. In one embodimentof the invention, the method includes the step of positioning themicrowave energy delivery applicator over an axilla. In one embodimentof the invention, the method includes the step of acquiring skin withina suction chamber. In one embodiment of the invention, the methodincludes the step of activating a vacuum pump. In one embodiment of theinvention, the method includes the step of deactivating a vacuum pump torelease skin. In one embodiment of the invention, the method includesthe step of securing skin tissue proximate to the microwave energydelivery applicator. In one embodiment of the invention, the methodincludes the step of securing skin tissue proximate to the microwaveenergy delivery applicator by applying suction to the skin tissue. Inone embodiment of the invention, the method includes the step ofsecuring skin tissue proximate to the microwave energy deliveryapplicator includes the step of at least partially acquiring the skintissue within a suction chamber adjacent to the energy deliveryapplicator. In one embodiment of the invention, the method includes thestep of using a lubricant to enhance vacuum. In one embodiment of theinvention, the method includes the step of securing skin tissueproximate to the microwave energy delivery applicator includes the stepof elevating the skin tissue. In one embodiment of the invention, themethod includes the step of securing skin tissue proximate to themicrowave energy delivery applicator includes the step of brining skinin contact with cooling. In one embodiment of the invention, the methodincludes the step of activating a vacuum pump to acquire the skin withina suction chamber.

In one embodiment, disclosed herein is a system for the application ofmicrowave energy to a tissue, including a signal generator adapted togenerate a microwave signal having predetermined characteristics; anapplicator connected to the generator and adapted to apply microwaveenergy to tissue, the applicator comprising one or more microwaveantennas and a tissue interface; a vacuum source connected to the tissueinterface; a cooling source connected to said tissue interface; and acontroller adapted to control the signal generator, the vacuum source,and the coolant source. In some embodiments, the microwave signal has afrequency in the range of between about 4 GHz and about 10 GHz, betweenabout 5 GHz and about 6.5 GHz, or about 5.8 GHz. The system can furthercomprise an amplifier connected between the signal generator and theapplicator. The microwave antenna may comprise an antenna configured toradiate electromagnetic radiation polarized such that an E-fieldcomponent of the electromagnetic radiation is substantially parallel toan outer surface of the tissue. In some embodiments, the microwaveantenna comprises a waveguide antenna. The antenna may comprise anantenna configured to radiate in TE10 mode, and/or TEM mode. The tissueinterface can be configured to engage and hold skin. The skin is of theaxillary region in some embodiments. The microwave antenna may comprisean antenna configured to radiate electromagnetic radiation polarizedsuch that an E-field component of the electromagnetic radiation isparallel to an outer surface of the tissue.

In some embodiments, the tissue interface comprises a cooling plate anda cooling chamber positioned between the cooling plate and the microwaveantenna. In some embodiments, the cooling plate has a dielectricconstant between about 2 and 15. The vacuum source can be configured tosupply vacuum pressure to the tissue interface. In some embodiments, thevacuum pressure is between about 400 mmHg to about 750 mmHg, or about650 mmHg in some embodiments. The cooling source can be configured tosupply a coolant to the tissue interface. The coolant can be a coolingfluid, which in some embodiments has a dielectric constant of betweenabout 70 and 90, about 80, between about 2 and 10, or about 2. In someembodiments, the cooling fluid can have a temperature of between about−5° C. and 40° C., 10° C. and 25° C., or about 22° C. In someembodiments, the cooling fluid has a flow rate through at least aportion of the tissue interface of between about 100 mL and 600 mL persecond, or between about 250 mL and 450 mL per second. In someembodiments, the cooling fluid is configured to flow through the tissueinterface at a velocity of between 0.18 and 0.32 meters per second. Thecooling fluid can be selected from, e.g., glycerin, vegetable oil,isopropyl alcohol, water, water mixed with alcohol, or othercombinations in some embodiments. The cooling source may comprise athermoelectric module. In some embodiments, the tissue comprises a firstlayer and a second layer, the second layer below the first layer,wherein the controller is configured such that the system deliversenergy such that a peak power loss density profile is created in thesecond layer.

In another embodiment, disclosed is an apparatus for deliveringmicrowave energy to target tissue, the apparatus comprising a tissueinterface; a microwave energy delivery device; a cooling elementpositioned between the tissue interface and the microwave energy device,the cooling element comprising a cooling plate positioned at the tissueinterface; and a cooling fluid positioned between the cooling elementand the microwave delivery device, the cooling fluid having a dielectricconstant greater than a dielectric constant of the cooling element. Insome embodiments, the tissue interface comprises a tissue acquisitionchamber, which can be a vacuum chamber in some embodiments. The coolingplate may be made of ceramic. In some embodiments, the cooling plate isconfigured to contact a skin surface about the target tissue, cool theskin tissue, and physically separate the skin tissue from the coolingfluid. In some embodiments, the microwave energy delivery devicecomprises a microwave antenna, which may be a waveguide antenna in someembodiments.

In another embodiment, disclosed is an apparatus for deliveringmicrowave energy to a target region in tissue, the apparatus comprising:a tissue interface having a tissue acquisition chamber; a coolingelement having a cooling plate; and a microwave energy delivery devicehaving a microwave antenna. In some embodiments, the tissue acquisitionchamber comprises a vacuum chamber adapted to elevate tissue, includingthe target region, and bring the tissue in contact with the coolingelement. In some embodiments, the vacuum chamber has a racetrack shapecomprising a first side and a second side, the first and second sidesparallel to each other, and a first end and a second end, the first andsecond ends having arcuate shapes. In some embodiments, the coolingplate is configured to contact a skin surface above the target tissue,cool the skin tissue, and physically separate the skin tissue from themicrowave energy delivery device. The cooling plate may be substantiallytransparent to microwave energy. In some embodiments, the microwaveantenna is configured to deliver sufficient energy to the target regionto create a thermal effect. In some embodiments, the microwave antennacomprises a waveguide antenna.

Also disclosed, in one embodiment, is an apparatus for deliveringmicrowave energy to a target region in tissue, the apparatus comprisinga vacuum chamber adapted to elevate tissue including the target regionand bring the tissue into contact with a cooling plate, wherein thecooling plate is adapted to contact a skin surface above the targetregion, cool the skin surface, and physically separate the skin tissuefrom the microwave energy delivery device; and a microwave antennaconfigured to deliver sufficient energy to the target region to create athermal effect. In some embodiments, the vacuum chamber may have a racetrack shape comprising a first side and a second side, the first andsecond sides parallel to each other; and a first end and a second end,the first and second ends having arcuate shapes. In some embodiments,the cooling plate is substantially transparent to microwave energy. Insome embodiments, the microwave antenna is configured to deliversufficient energy to the target region to create a thermal effect. Insome embodiments, the microwave antenna comprises a waveguide antenna.In some embodiments, the microwave antenna is configured to generate aradiation pattern having a peak at the target region.

Also disclosed, in one embodiment, is a system for coupling microwaveenergy into tissue, the system comprising a microwave antenna, a fluidchamber positioned between the microwave antenna and the tissue, and acooling plate positioned between the cooling chamber and the tissue. Inone embodiment, the system further comprises at least one fieldspreader. The field spreader may be positioned within the fluid chamberbetween the waveguide and the cooling plate. The field spreader may beconfigured to facilitate laminar flow of fluid through the fluidchamber. In one embodiment, the field spreader may be configured toprevent one or more of eddy currents or air bubbles within the coolingfluid. In one embodiment, the system may further comprise a coolingfluid selected to maximize thermal transfer while minimizing microwavereflections. The cooling fluid may be selected from the group consistingof alcohol, glycerol, ethylene glycol, deionized water, a germicide, andvegetable oil. In one embodiment, the microwave antenna may a waveguideincluding a dielectric filler selected to generate a field having aminimal electric field perpendicular to a surface of the tissue at apredetermined frequency. In one embodiment, the fluid chamber has ashape configured to facilitate laminar flow of cooling fluidtherethrough. The fluid chamber may be rectangular shaped. In someembodiments, the cooling plate is thermally conductive and substantiallytransparent to microwave energy.

In another embodiment, a method of creating a tissue effect in a targettissue layer is disclosed, comprising the steps of: irradiating thetarget tissue layer and a first tissue layer through a skin surface withelectromagnetic energy having predetermined frequency and electric fieldcharacteristics, wherein the first tissue layer is above the targettissue layer, the first tissue layer being adjacent to a surface of theskin; and generating a power loss density profile, wherein the powerloss density profile has a peak power loss density in a region of thetarget tissue layer. In one embodiment, the method further comprises thestep of identifying a patient desiring a reduction in sweat production.In other embodiments, the method further comprises the step ofidentifying a patient desiring a reduction in cellulite, identifying apatient with hyperhidrosis, identifying a patient with telangiectasias,identifying a patient with varicose veins, or identifying a patientdesiring hair removal. In another embodiment, the method furthercomprises the step of removing heat from the first tissue layer. In oneembodiment, the method further comprises the step of removing heat fromthe tissue layer. In one embodiment, the tissue effect comprises alesion. The lesion may have an origin in the target tissue layer. In oneembodiment, the origin of the lesion is in the region of the targettissue layer having the peak power loss density. In one embodiment, themethod further comprises the step of removing sufficient heat from thefirst layer to prevent the lesion from growing into the first layer,wherein the step of removing heat from the first tissue layer comprisescooling the skin surface. In one embodiment, the target tissue layer maycomprise the dermis, a deep layer of the dermis, or a glandular layer.In one embodiment, the electromagnetic energy has an electric fieldcomponent which is substantially parallel to at least a portion of theskin surface. The electromagnetic energy may have an electric fieldcomponent which is parallel to at least a portion of the skin surface.In some embodiments, the electromagnetic energy radiates in a TE₁₀ modeor TEM mode. In some embodiments, the electromagnetic energy has afrequency in the range between about 4 GHz and 10 Ghz, between 5 GHz and6.5 GHz, or approximately 5.8 GHz. In one embodiment, theelectromagnetic energy generates heat in the target tissue by dielectricheating. In one embodiment, the power loss density is generated by astanding wave pattern in the target tissue layer and the first tissuelayer. In one embodiment, the standing wave pattern has a constructiveinterference peak in the region of the target tissue layer. The standingwave pattern may have a constructive interference minimum in the firsttissue layer.

In another embodiment, disclosed is a method of creating a lesion in atarget tissue layer in the absence of cooling, wherein the target tissuelayer is below a first tissue layer, the first tissue layer beingadjacent to a skin surface, the method comprising the steps of:irradiating the target tissue layer and a first tissue layer through askin surface with electromagnetic energy having predetermined frequencyand electric field characteristics, wherein the first tissue layer isabove the target tissue layer, the first tissue layer being adjacent toa surface of the skin; and generating a power loss density profile,wherein the power loss density profile has a peak power loss density ina region of the target tissue layer. In one embodiment, the lesion hasan origin in the target tissue layer. In some embodiments, the targettissue layer comprises the dermis, a deep layer of the dermis, or aglandular layer. In one embodiment, the electromagnetic energy has anelectric field component which is substantially parallel to at least aportion of the skin surface. In one embodiment, the electromagneticenergy has an electric field component which is substantially parallelto at least a portion of the skin surface. In one embodiment, theelectromagnetic energy has an electric field component which is parallelto at least a portion of the skin surface. In some embodiments, theelectromagnetic energy radiates in a TE₁₀ mode or a TEM mode. In someembodiments, the electromagnetic energy has a frequency in the range ofbetween about 4 GHz and 10 GHz, 5 GHz and 6.5 GHz, or approximately 5.8GHz. The electromagnetic energy may generate heat in the target tissueby dielectric heating. In one embodiment, the power loss density isgenerated by a standing wave pattern in the target tissue layer and thefirst tissue layer. The standing wave pattern may have a constructiveinterference peak in the region of the target tissue layer or in thefirst tissue layer. In one embodiment, the origin of the lesion is inthe region of the target tissue layer having the peak power lossdensity.

In another embodiment, disclosed is a method of generating heat in atarget tissue layer wherein the heat is sufficient to create a lesion inor proximate to the target tissue layer, wherein the target tissue layeris below a first tissue layer, the first tissue layer being adjacent toa skin surface, the method comprising the steps of: irradiating thetarget tissue layer and the first tissue layer through the skin surfacewith electromagnetic energy having predetermined frequency and electricfield characteristics; and generating a power loss density profilewherein the power loss density profile has a peak power loss density ina region of the target tissue layer. In one embodiment, the lesion hasan origin in the target tissue layer. In some embodiment, the targettissue layer comprises the dermis, a deep layer of the dermis or aglandular layer. In one embodiment, the method further comprises thestep of removing heat from the first tissue layer. In one embodiment,the method further comprises the step of removing sufficient heat fromthe first layer to prevent the lesion from growing into the first layer,wherein the step of removing heat from the first tissue layer comprisescooling the skin surface. In some embodiment, the electromagnetic energyhas an electric field component which is substantially parallel to atleast a portion of the skin surface, while in other embodiments, theelectric field component is parallel to at least a portion of the skinsurface. In some embodiments, the electromagnetic energy radiates in aTE₁₀ mode or TEM mode. In some embodiments, the electromagnetic energyhas a frequency in the range of between about 4 GHz and 10 GHz, 5 GHzand 6.5 GHz, or approximately 5.8 GHz. In one embodiment, theelectromagnetic energy generates heat in the target tissue by dielectricheating. In one embodiment, the power loss density is generated by astanding wave pattern in the target tissue layer and the first tissuelayer. In one embodiment, the power loss density is generated by astanding wave pattern in the target tissue layer and the first tissuelayer. In some embodiments, the standing wave pattern has a constructiveinterference peak in the region of the target tissue layer or in thefirst tissue layer. In one embodiment, the origin of the lesion is inthe region of the target tissue layer having the peak power lossdensity. In one embodiment, the heat is sufficient to destroy bacteriawithin the target tissue. In some embodiments, the method furthercomprises the step of identifying a patient with acne or identifying apatient desiring a reduction of sweat production.

In another embodiment, disclosed is a method of generating heat in atarget tissue layer in the absence of cooling wherein the heat issufficient to create a tissue effect in or proximate to the targettissue layer, wherein the target tissue layer is below a first tissuelayer, the first tissue layer being adjacent to a skin surface, themethod comprising the steps of: irradiating the target tissue layer andthe first tissue layer through the skin surface with electromagneticenergy having predetermined frequency and electric fieldcharacteristics; and generating a power loss density profile wherein thepower loss density profile has a peak power loss density in a region ofthe target tissue layer. In one embodiment, the heat is sufficient togenerate a lesion having an origin in the target tissue layer. In someembodiments, the target tissue layer comprises the dermis, deep layer ofthe dermis or glandular layer. In one embodiment, the electromagneticenergy has an electric field component which is substantially parallelto at least a portion of the skin surface, while in another embodiment,the electric field component is parallel to at least a portion of theskin surface. In some embodiments, the electromagnetic energy radiatesin a TE₁₀ mode or a TEM mode. In some embodiments, the electromagneticenergy has a frequency in the range of between about 4 GHz and 10 GHz, 5GHz and 6.5 GHz, or about 5.8 GHz. In one embodiment, theelectromagnetic energy generates heat in the target tissue by dielectricheating. In one embodiment, the power loss density is generated by astanding wave pattern in the target tissue layer and the first tissuelayer. In some embodiments, the standing wave pattern has a constructiveinterference peak in the region of the target tissue layer or in thefirst tissue layer. In one embodiment, the standing wave pattern has aconstructive interference minimum in the first tissue layer. In oneembodiment, the origin of the lesion is in the region of the targettissue layer having the peak power loss density.

Also disclosed herein, in another embodiment is a method of generating atemperature profile in tissue wherein the temperature profile has a peakin a target tissue layer, wherein the target tissue layer is below afirst tissue layer, the first tissue layer being adjacent to a skinsurface, the method comprising the steps of: irradiating the targettissue layer and the first tissue layer through the skin surface withelectromagnetic energy having predetermined frequency and electric fieldcharacteristics; and generating a power loss density profile wherein thepower loss density profile has a peak power loss density in a region ofthe target tissue layer. In some embodiments, the target tissue layercomprises the dermis, a deep layer of the dermis or a glandular layer.In one embodiment, the method further comprises the step of removingheat from the first tissue layer. In one embodiment, the electromagneticenergy has an electric field component which is substantially parallelto at least a portion of the skin surface. In one embodiment, theelectromagnetic energy has an electric field component which is parallelto at least a portion of the skin surface. In some embodiments, theelectromagnetic energy radiates in a TE₁₀ mode or TEM mode. In someembodiments, the electromagnetic energy has a frequency in the range ofbetween about 4 GHz and 10 GHz, between about 5 GHz and 6.5 GHz, or ofapproximately 5.8 GHz. In one embodiment, the electromagnetic energygenerates heat in the target tissue by dielectric heating. In oneembodiment, the power loss density is generated by a standing wavepattern in the target tissue layer and the first tissue layer. Thestanding wave pattern may have a constructive interference peak in theregion of the target tissue layer. The standing wave pattern may have aconstructive interference minimum in the first tissue layer. In oneembodiment, the peak temperature is in the region of the target tissuelayer having the peak power loss density.

In another embodiment, disclosed herein is a method of generating atemperature profile in tissue in the absence of cooling wherein thetemperature profile has a peak in a target tissue layer, wherein thetarget tissue layer is below a first tissue layer, the first tissuelayer being adjacent to a skin surface, the method comprising the stepsof: irradiating the target tissue layer and the first tissue layerthrough the skin surface with electromagnetic energy havingpredetermined frequency and electric field characteristics; andgenerating a power loss density profile wherein the power loss densityprofile has a peak power loss density in a region of the target tissuelayer. In some embodiments, the target tissue layer comprises thedermis, a deep layer of the dermis or a glandular layer. In someembodiments, the electromagnetic energy has an electric field componentwhich is substantially parallel to at least a portion of the skinsurface or which is parallel to at least a portion of the skin surface.In some embodiments, the electromagnetic energy radiates in a TE₁₀ modeor a TEM mode. In some embodiments, the electromagnetic energy has afrequency in the range of between about 4 GHz and 10 GHz, 5 GHz and 6.5GHz or approximately 5.8 GHz. In one embodiment, the electromagneticenergy generates heat in the target tissue by dielectric heating. In oneembodiment, the power loss density is generated by a standing wavepattern in the target tissue layer and the first tissue layer. Thestanding wave pattern may have a constructive interference peak in theregion of the target tissue layer. The standing wave pattern may have aconstructive interference minimum in the first tissue layer. In oneembodiment, the peak temperature is in the region of the target tissuelayer having the peak power loss density.

In another embodiment, disclosed is a method of creating a lesion in afirst layer of tissue, the first layer having an upper portion adjacentan external surface of the skin and a lower portion adjacent a secondlayer of the skin, the method comprising the steps of: exposing theexternal surface of the skin to microwave energy having a predeterminedpower, frequency, and electric field orientation; generating an energydensity profile having a peak in the lower portion of the first layer;and continuing to expose the external surface of the skin to themicrowave energy for a time sufficient to create a lesion, wherein thelesion begins in the peak energy density region. In one embodiment, thefirst layer of skin has a first dielectric constant and the second layerof skin has a second dielectric constant, wherein the first dielectricconstant is greater than the second dielectric constant. In oneembodiment, the first layer has a dielectric constant greater than about25 and the second layer has a dielectric constant less than or equal toabout 10. In one embodiment, the first layer comprises at least aportion of a dermis layer. In some embodiments, the second layercomprises at least a portion of a hypodermis layer or at least a portionof a glandular layer.

Also disclosed herein is a method of creating a lesion in the skinwherein the skin has at least an external surface, a first layer belowthe external surface and a second layer, the method comprising the stepsof: positioning a device adapted to radiate electromagnetic energyadjacent the external surface; radiating electromagnetic energy from thedevice, the microwave energy having an electric field component which issubstantially parallel to a region of the external surface; andgenerating a standing wave pattern in the first layer, the standing wavepattern having a constructive interference peak in the first layer,wherein a distance from the constructive interference peak to the skinsurface is greater than a distance from the constructive interferencepeak to an interface between the first layer and the second layer. Inone embodiment, the electromagnetic energy comprises microwave energy.In one embodiment, the constructive interference peak is adjacent theinterface. In one embodiment, the first layer has a first dielectricconstant and the second layer has a second dielectric constant, whereinthe first dielectric constant is greater than the second dielectricconstant. In one embodiment, the first layer has a dielectric constantgreater than about 25 and the second layer has a dielectric constantless than or equal to about 10. In one embodiment, the first layercomprises at least a portion of a dermis layer. In some embodiments, thesecond layer comprises at least a portion of a hypodermis layer or atleast a portion of a glandular layer.

In another embodiment, disclosed is a method of creating a temperaturegradient in the skin wherein the skin has at least an external surface,a first layer below the external surface and a second layer, the methodcomprising the steps of: positioning a device adapted to radiateelectromagnetic energy adjacent the external surface; radiatingelectromagnetic energy from the device, the microwave energy having anelectric field component which is substantially parallel to a region ofthe external surface; and generating a standing wave pattern in thefirst layer, the standing wave pattern having a constructiveinterference peak in the first layer, wherein a distance from theconstructive interference peak to the skin surface is greater than adistance from the constructive interference peak to an interface betweenthe first layer and the second layer.

In another embodiment, disclosed is a method of creating a lesion in adermal layer of the skin, the dermal layer having an upper portionadjacent an external surface of the skin and a lower portion adjacent asubdermal layer of the skin, the method comprising the steps of:exposing the external surface to microwave energy having a predeterminedpower, frequency, and electric field orientation; generating a peakenergy density region in the lower portion of the dermal layer; andcontinuing to radiate the skin with the microwave energy for a timesufficient to create a lesion, wherein the lesion begins in the peakenergy density region.

In another embodiment, disclosed is a method of creating a lesion in adermal layer of the skin wherein the skin has at least a dermal layerand a subdermal layer, the method comprising the steps of: positioning adevice adapted to radiate microwave energy adjacent an external surfaceof the skin; and radiating microwave energy having an electric fieldcomponent which is substantially parallel to a region of the externalsurface of the skin above the dermal layer, wherein the microwave energyhas a frequency which generates a standing wave pattern in the dermallayer, the standing wave pattern having a constructive interference peakin the dermal layer in close proximity to an interface between thedermal layer and the subdermal layer.

In another embodiment, disclosed herein is a method of creating a lesionin a dermal layer of the skin wherein the skin has at least a dermallayer and a subdermal layer, the method comprising the steps of:positioning a device adapted to radiate microwave energy adjacent anexternal surface of the skin; radiating microwave energy having anelectric field component which is substantially parallel to a region ofthe external surface of the skin above the dermal layer, wherein themicrowave energy has a frequency which generates a standing wave patternin the dermal layer, the standing wave pattern having a constructiveinterference peak in the dermal layer in close proximity to an interfacebetween the dermal layer and the subdermal layer; and heating the lowerportion of the dermal region using the radiated microwave energy tocreate the lesion. In one embodiment, a center of the lesion ispositioned at the constructive interference peak.

In another embodiment, disclosed is a method of heating a tissuestructure located in or near a target tissue layer, wherein the targettissue layer is below a first tissue layer, the first tissue layer beingadjacent a skin surface, the method comprising the steps of: irradiatingthe target tissue layer and the first tissue layer through the skinsurface with electromagnetic energy having predetermined frequency andelectric field characteristics; and generating a power loss densityprofile wherein the power loss density profile has a peak power lossdensity in a region of the target tissue layer. In one embodiment, thetissue structure comprises a sweat gland. In one embodiment, heating thetissue structure is sufficient to destroy a pathogen located in or nearthe tissue structure. The pathogen may be bacteria. In some embodiments,the tissue structure is a sebaceous gland or at least a portion of ahair follicle. In some embodiments, the tissue structure may be selectedfrom the group consisting of: telangiectasias, cellulite, varicoseveins, and nerve endings. In one embodiment, heating the tissuestructure is sufficient to damage the tissue structure. In oneembodiment, the heat generates a lesion having an origin in the targettissue layer. The lesion grows to include the tissue structure. In oneembodiment, the method further comprises the step of removing sufficientheat from the first layer to prevent the lesion from growing into thefirst layer. Removing sufficient heat from the first layer may comprisecooling the skin surface. In some embodiments, the target tissue layermay comprise a deep layer of the dermis or a glandular layer. In someembodiments, the electromagnetic energy has an electric field componentwhich is substantially parallel to at least a portion of the skinsurface or is parallel to at least a portion of the skin surface. Insome embodiments, the electromagnetic energy radiates in a TE₁₀ mode orTEM mode. In some embodiments, the electromagnetic energy has afrequency in the range of between about 4 GHz and 10 GHz, 5 GHz and 6.5GHz, or approximately 5.8 GHz. In one embodiment, the electromagneticenergy generates heat in the target tissue by dielectric heating. In oneembodiment, the power loss density is generated by a standing wavepattern in the target tissue layer and the first tissue layer. Thestanding wave pattern may have a constructive interference peak in theregion of the target tissue layer. The standing wave pattern may have aconstructive interference minimum in the first tissue layer. In oneembodiment, the origin of the lesion is in the region of the targettissue layer having the peak power loss density. In one embodiment, thelesion continues to grow through thermal conductive heating afterelectromagnetic energy is no longer applied. In one embodiment, thetarget tissue structure is heated primarily as a result of the thermalconductive heating.

In another embodiment, disclosed herein is a method of raising thetemperature of at least a portion of a tissue structure located below aninterface between a dermal layer and subdermal layer in skin, the dermallayer having an upper portion adjacent an external surface of the skinand a lower portion adjacent a subdermal region of the skin, the methodcomprising the steps of: radiating the skin with microwave energy havinga predetermined power, frequency and e-field orientation; generating apeak energy density region in the lower portion of the dermal layer;initiating a lesion in the peak energy density region by dielectricheating of tissue in the peak energy density region; enlarging thelesion, wherein the lesion is enlarged, at least in part, by conductionof heat from the peak energy density region to surrounding tissue;removing heat from the skin surface and at least a portion of the upperportion of the dermal layer; and continuing to radiate the skin with themicrowave energy for a time sufficient to extend the lesion past theinterface and into the subdermal layer. In one embodiment, the tissuestructure comprises a sweat gland.

Also disclosed herein in another embodiment is a method of raising thetemperature of at least a portion of a tissue structure located below aninterface between a dermal layer and a subdermal layer of skin, whereinthe dermal layer has an upper portion adjacent an external surface ofthe skin and a lower portion adjacent a subdermal region of the skin,the method comprising the steps of: positioning a device adapted toradiate microwave energy adjacent the external surface of the skin;radiating microwave energy having an electric field component which issubstantially parallel to a region of the external surface above thedermal layer, wherein the microwave energy has a frequency whichgenerates a standing wave pattern in the dermal layer, the standing wavepattern having a constructive interference peak in the lower portion ofthe dermal layer; creating a lesion in the lower portion of the dermalregion by heating tissue in the lower portion of the dermal region usingthe radiated microwave energy; removing heat from the skin surface andat least a portion of the upper portion of the dermal layer to preventthe lesion from spreading into the upper portion of the dermal layer;and ceasing the radiating after a first predetermined time, thepredetermined time being sufficient to raise the temperature of thetissue structure. In some embodiments, the first predetermined timecomprises a time sufficient to deposit enough energy in said lowerportion of the dermal layer to enable said lesion to spread into thesubdermal region or a time sufficient to enable heat generated by saidradiation to spread to the tissue structure. In one embodiment, the stepof removing heat further comprises continuing to remove heat for apredetermined time after the step of ceasing said radiating. In oneembodiment, the constructive interference peak is located on a dermalside of the interface between the dermal layer and the subdermal layer.In one embodiment, the lesion starts at the constructive interferencepeak.

In another embodiment, disclosed herein is a method of controlling theapplication of microwave energy to tissue, the method comprising thesteps of: generating a microwave signal having predeterminedcharacteristics; applying the microwave energy to tissue, through amicrowave antenna and a tissue interface operably connected to themicrowave antenna; supplying a vacuum pressure to the tissue interface;and supplying cooling fluid to the tissue interface. In someembodiments, the microwave signal has a frequency in the range ofbetween about 4 GHz and 10 GHz, between about 5 GHz and 6.5 GHz, orapproximately 5.8 GHz. In one embodiment, the microwave antennacomprises an antenna configured to radiate electromagnetic radiationpolarized such that an E-field component of the electromagneticradiation is substantially parallel to an outer surface of the tissue.The microwave antenna may comprise a waveguide antenna. In someembodiments, the microwave antenna comprises an antenna configured toradiate in TE₁₀ mode or in TEM mode. In one embodiment, the tissueinterface is configured to engage and hold skin. The skin may be in theaxillary region. In one embodiment, the microwave antenna comprises anantenna configured to radiate electromagnetic radiation polarized suchthat an E-field component of the electromagnetic radiation is parallelto an outer surface of the tissue. In one embodiment, the tissueinterface comprises a cooling plate and a cooling chamber positionedbetween the cooling plate and the microwave antenna. In one embodiment,the cooling plate has a dielectric constant between about 2 and 15. Inone embodiment, the vacuum source is configured to supply vacuumpressure to the tissue interface. In some embodiments, the vacuumpressure is between about 400 mmHg to about 750 mmHg, or about 650 mmHgIn one embodiment, the cooling source is configured to supply a coolantto the tissue interface. In one embodiment, the coolant is a coolingfluid. In some embodiments, the cooling fluid has a dielectric constantof between about 70 and 90, or about 80, or between about 2 and 10, orabout 2. In some embodiments, the cooling fluid has a temperature ofbetween about −5° C. and 40° C. or between about 10° C. and 25° C. Inone embodiment, the cooling fluid has a temperature of about 22° C. Insome embodiments, the cooling fluid has a flow rate through at least aportion of the tissue interface of between about 100 mL and 600 mL persecond or between about 250 mL and 450 mL per second. In one embodiment,the cooling fluid is configured to flow through the tissue interface ata velocity of between about 0.18 and 0.32 meters per second. In oneembodiment, the cooling fluid is selected from the group consisting ofglycerin, vegetable oil, isopropyl alcohol, and water, while in anotherembodiment, the cooling fluid is selected from the group consisting ofwater and water mixed with an alcohol.

Also disclosed, in another embodiment, is a method of positioning tissueprior to treating the tissue using radiated electromagnetic energy, themethod comprising positioning a tissue interface adjacent a skinsurface; engaging the skin surface in a tissue chamber of the tissueinterface; substantially separating a layer comprising at least onelayer of the skin from a muscle layer below the skin; and holding theskin surface in the tissue chamber. In one embodiment, the tissueinterface comprises a tissue chamber, the tissue chamber having at leastone wall and a tissue-contacting surface. In one embodiment, at least aportion of the tissue surface comprises a cooling plate positioned inthe tissue chamber. In one embodiment, the tissue chamber has an aspectratio in the range of between about 1:1 and 3:1, while in anotherembodiment, the tissue chamber has an aspect ratio of about 2:1. In oneembodiment, the tissue chamber has a tissue acquisition angle betweenthe wall and the tissue surface, the tissue acquisition angle being inthe range of between about 2 degrees and approximately 45 degrees, whilein another embodiment, the tissue acquisition angle is in the range ofbetween about 5 degrees and approximately 20 degrees. In one embodiment,the tissue chamber has a tissue acquisition angle between the wall andthe tissue surface, the tissue acquisition angle is about 20 degrees.

The various embodiments described herein can also be combined to providefurther embodiments. Related methods, apparatuses and systems utilizingmicrowave and other types of therapy, including other forms ofelectromagnetic radiation, and further details on treatments that may bemade with such therapies, are described in the above-referencedprovisional applications to which this application claims priority, theentireties of each of which are hereby incorporated by reference: U.S.Provisional Patent Application No. 60/912,889, entitled “Methods andApparatus for Reducing Sweat Production,” filed Apr. 19, 2007, U.S.Provisional Patent Application No. 61/013,274, entitled “Methods,Delivery and Systems for Non-Invasive Delivery of Microwave Therapy,”filed Dec. 12, 2007, and U.S. Provisional Patent Application No.61/045,937, entitled “Systems and Methods for Creating an Effect UsingMicrowave Energy in Specified Tissue,” filed Apr. 17, 2008. While theabove-listed applications may have been incorporated by reference forparticular subject matter as described earlier in this application,Applicants intend the entire disclosures of the above-identifiedapplications to be incorporated by reference into the presentapplication, in that any and all of the disclosures in theseincorporated by reference applications may be combined and incorporatedwith the embodiments described in the present application.

While this invention has been particularly shown and described withreferences to embodiments thereof, it will be understood by thoseskilled in the art that various changes in form and details may be madetherein without departing from the scope of the invention. For all ofthe embodiments described above, the steps of the methods need not beperformed sequentially.

What is claimed is:
 1. A system for the application of microwave energy to a tissue, comprising: a signal generator adapted to generate a microwave signal having predetermined characteristics; an applicator connected to the generator and adapted to apply microwave energy to tissue, the applicator comprising one or more microwave antennas and a tissue interface; a vacuum source connected to the tissue interface; a cooling source connected to said tissue interface; and a controller adapted to control the signal generator, the vacuum source, and the coolant source.
 2. An apparatus for delivering microwave energy to target tissue, the apparatus comprising: a tissue interface; a microwave energy delivery device; a cooling element positioned between the tissue interface and the microwave energy device, the cooling element comprising a cooling plate positioned at the tissue interface; and a cooling fluid positioned between the cooling element and the microwave delivery device, the cooling fluid having a dielectric constant greater than a dielectric constant of the cooling element.
 3. A method of creating a tissue effect in a target tissue layer, comprising the steps of: irradiating the target tissue layer and a first tissue layer through a skin surface with electromagnetic energy having predetermined frequency and electric field characteristics, wherein the first tissue layer is above the target tissue layer, the first tissue layer being adjacent to a surface of the skin; and generating a power loss density profile, wherein the power loss density profile has a peak power loss density in a region of the target tissue layer. 